531 Reference APIs: GeoNames, Wikipedia and CrunchBase

Our API directory now includes 531 reference APIs. The newest is the CanLII API. The most popular, in terms of mashups, is the GeoNames API. We list 88 GeoNames mashups. Below you'll find some more stats from the directory, including the entire list of reference APIs.

In terms of the technical details, REST and XML lead the way. There are 334 reference REST APIs and 167 reference SOAP APIs. Our directory lists 391 reference XML APIs and 241 reference JSON APIs.

The most common tags within reference are 53 science reference APIs, 51 search reference APIs and 43 government reference APIs.

On the mashup side, we list 405 reference mashups. We named Baby Name Meanings as mashup of the day last week.

For reference, here is a list of all 531 reference APIs.

  4:14 XML Bible API: Christian bible verse service

  4GuysFromRolla.com API: ASP.NET FAQ service

  Abbreviations API: Abbreviated words services

  Acromine API: Acronym look-up and text mining service

  ActBlue API: Democratic fundraising service

  Activism Network Community API: Online activism network and community

  AFD Software Postcode Everywhere API: UK address and bank information service

  AHDS Identifier Resolver API: UK electronic research data repository

  AIDSinfo API: Government info on HIV/AIDS treatment

  AIMS Address API: Johnson County Kansas address lookup service

  AllAreaCodes API: Area code lookup service

  Amazonca API: Online barcode database

  American Bible Society BibleSearch API: Bible access and search service

  Anime News Network Encylopedia API: Online Anime Encyclopedia Service

  Aonaware Dictionary API: Dictionary lookup service

  Aqua.io API: Standardized healthcare code reference service

  Archives Hub API: UK research archive

  art.sy API: Artwork information discovery service

  arXiv API: Academic research repository

  ASPECT Vocabulary Bank for Education API: Education vocabulary controlled lists

  Attempto RACE API: Text-based logical reasoning service

  Australian Business Register ABN Lookup API: Australian Business Number look-up service

  Australian Tourism Data Warehouse API: Australian tourism information service

  AutoAppMart API: In-car application marketplace

  Avalara API: Sales tax data service

  AVIN API: Wine tracking number repository

  Avvo API: Lawyer and doctor directory service

  Baby Names API: International baby naming services

  BankHolidays API: Swedish banking holiday lookup service

  BankLZ API: German bankcode lookup service

  Barcelona Bicing API: Bicing station data

  Barnivore API: Vegan alcohol guide

  Basic Local Alignment Search Tool API: Genome database search tool

  Bavarian Authorities Signpost API: Local information service for Bavaria

  BBAS Personal Data Repository API: Semantic data for scientific biographical information

  BBAW G2L API: Greek-Latin text transliteration service

  BBAW ISO-Date API: German and Italian text analysis service

  BBAW Places API: German text analysis and place name service

  BBS Scene API: Bulletin board system services

  Bearmini Public Holiday API: Japanese public holiday reference service

  Behind the Name API: First name etymology and history database

  Best Buy BBYOpen Stores API: Retail store data

  Biblia.com API: Online bible reference service

  BibServer API: Bibliographic metadata consolidation and sharing service

  Big Huge Thesaurus API: Thesaurus lookup services

  BigOven Recipe API: Recipes, grocery list, and nutrition API

  Billboard API: Music chart service

  Bing API: Online search services

  BIOBASE API: Biological research data repository

  BioCatalogue API: Life sciences web registry service

  BioGRID API: Biological reference search service

  BioMOBY API: Plant genome reference service

  Biomolecular Interaction Network Database API: Biomolecular database

  Biosemantics JANE API: Journal and author name service

  Black Book Online API: U.S. public record search service

  Boliven API: Online repository of medical device information

  Boliven Publications API: Patent and scientific document Portal

  Bookshare API: Accessible Books For Readers with Print Disabilities

  Brain Maps API: Brain section images

  Brewery DB API: Your Complete Brewery and Beer API

  burrp API: Local business search service

  Business Profiles API: Business operating information service

  Business.gov API: US government small business resources

  Byomei API: Japanese disease reference service

  Callook API: US amateur radio callsign lookup

  CalorieKing API: Food information service

  Cambridge Journals Online API: Cambridge University Press collections

  Cambridge Lookup/Ibis Web Service API: Online Contact Retrieval Service

  Cambridge University Library API: Library catalog and services

  CanLII API: Canadian legal database

  CarJam API: New Zealand car facts history service

  CarQuery API: Automobile information

  CatalogWS API: Academic library

  CDYNE 411 API: Directory assistance service

  CDYNE Death Index API: Access to the Social Security Death Index

  CDYNE Demographics API: Neighborhood level demographics service

  CEERN API: Conservation and Environment Resource Database

  CENSUS.IRE.ORG API: 2010 census data access service

  Cevir Turkish-English Dictionary API: Turkish-English Dictionary look up service

  Cheeso's Looky Book Service API: Simple book search

  Chemcaster API: Cheminformatics management Platform

  ChemSpider API: Chemical structure database

  China Historical GIS API: Chinese history and geography information service

  Chinese PostalCodeSearch API: Chinese postal code lookup service

  Chronicling America API: Archive of US newspapers

  CitedIn API: PubMed citation tracking service

  CiteULike API: Citation management service

  City and State by Zip Code API: Address lookup service

  City of Helsinki Service Map API: Helsinki information and service resource map

  CityGroups API: Local public directory

  ClinicalTrials.gov API: Clinical trials database and registry

  Clodoc API: Clojure programming Documentation service

  ClojureDocs API: Clojure programming language example repository

  Collins Dictionary API: Online dictionary

  CommonDataHub API: Universal data standards repository

  Complexity Intelligence Spell Checker API: Spelling correction and recommendation service

  Comprehensive Knowledge Archive Network API: Community driven open knowledge database

  Conversions API: Online calculator and measurment converter

  Cooper-Hewitt National Design Museum API: Design museum collections database

  Copac SALT recommender API: Library resource recommendation service

  CoPub API: Medical research text mining service

  Cortera API: Business information and research data

  Cortera Business Vitals API: Basic company information Web Service

  Countries and Time Zones API: Time zone information service

  CrossRef DOI Resolver API: Persistent identifier resolver

  CrunchBase API: Directory of companies, people, and investors

  CSA/NBII Biocomplexity Thesaurus API: Biocomplexity Thesaurus search service

  CSRHUB API: Corporate Social Responsibility ratings database

  D&B Direct API: Commercial business information service

  Daleeli Mobile API: Saudi Arabian business directory

  Data-Planet API: Statistical data service

  Data.be API: Business information service

  Data8 Companies House API: UK company search service

  Data8 Movers Identification API: Address checking and update service

  Datahotell API: Norway open government data

  Datanibble API: Quotes generator

  DayDetails API: On-this-date lookup service

  DBpedia API: Structured query interface to Wikipedia

  DBpedia Spotlight API: Semantic Text Annotation and Disambiguation

  DCMI Metadata Registry API: Metadata management service

  DDBC Authority Database API: Authoritative Buddhist people, place, and event name service

  Deduktiv ebaas distance API: UK postcodes service

  Deepdyve API: Scientific and medical journals

  Diablo 3 API: Diablo data service

  Dictionary Definitions API: Online dictionary

  Digital Public Library of America API: National digital library

  DigitalClassicist G-Tool API: Greek-to-Latin translation service

  DigitalNZ API: New Zealand metadata database

  Dun and Bradstreet Business Verification API: Research company background data

  Dun and Bradstreet Credit Check API: Credit quick check web service

  Dun and Bradstreet WorldBase Marketing Plus API: Business research services

  DuoShare Address Verification API: US address verification service

  DynaMed API: Medical clinic reference

  EBI CiteXplore API: Scientific publication and metadata retrieval

  eBibleicious API: Bible lookup service

  Ecolabel Index API: Ecolabel Database Tools

  Edmunds.com Inventory API: Specific automobile information via VIN

  Edoceo API: Assorted reference and conversion tools

  Education.com API: School test scores and other data

  eLife API: Biological sciences journal access service

  Elsevier Linked Data Repository API: Semantic metadata service

  Email Address Validator API: Email address validation service

  Encyclopedia of Life API: Biology Encyclopedia

  EnergyStar ABS API: Energy management and conservation service

  EnergyStar Third-Party Certification API: Energy efficiency certification processing service

  Enrycher API: Text analysis and keyword generation service

  ESV Bible Lookup API: Bible lookup service

  Europeana OpenSearch API: European museum collection metadata

  Excluded Parties List System API: List of entities ineligible for Federal contracts

  Exploring Surrey's past API: Surrey County historical resource

  Factual Places API: Open Data for sharing and reference tools

  FAO Fisheries and Aquaculture Fact Sheets API: Fisheries and aquaculture data service

  FatSecret API: Food, nutrition and recipe database and diet tools

  Fietstas API: Document and text processing service

  Fillbug API: Query by example service

  FinData API: Global financial information service

  FindPeopleFree API: Find UK residents and businesses by region

  Forvo API: Online word pronunciation guide

  FraudLabs AreaCodeWorld NPA NXX Area Code API: Geographical location service

  FRED API: US Federal Reserve Economic data

  Freebase API: Community driven open database

  FreeCite API: Bibliographic citations parsing service

  FreeCovers.net API: Album cover archive

  Frengly Translation API: Text translation service

  Freshmeat API: Open source application index

  FUTEF Wikipedia API API: Third party Wikipedia web service

  Fwix Location API: Business listing service

  GEMET API: Multi-language thesaurus management service

  Genability API: Electricity price data service

  Genetics Home Reference API: Genetics research site

  Genomic Name Server API: Bioinformatics database

  GeoNames API: Geographic name and postal code lookup

  GEPIR API: Get company contact information via bar code

  Getpincode API: Indian pincode search engine

  GlobalQuran API: Quran text and audio

  Glocal Focal US Mortality Data API: US government mortality data

  Glosbe API: Multilingual online dictionary and translation memory

  GMOD API: Remote Querying of Biological Databases

  Good Business Day Exchanges API: International exchange holidays and hours reference service

  Goodreads API: Book search and social book services

  Google Books API: Book search services

  Google Civic Information API: Civic information service

  Google Diacritize API: Language pronunciation tool

  Google Places API: Local business and point of interest service

  Gracenote API: Music and video metadata service

  Greek Republic Ministry of Finance GSIS API: Greek citizens and traders information service

  Gwinnett Roman Baptist Church Open Bible API: Bible excerpt service

  Harvard Dash API: Digital repository of scholarly articles

  Hathi Trust Data Distribution API: Library catalog search service

  Healthnotes API: Self-care Decision Support

  HIPAASpace API: HIPAA code lookup services

  HireRight API: Human resources hiring screening service

  Holidays Service API: Holiday dates lookup service

  Hosca BankFinder API: Find banks by zipcode

  How do you pronounce and use...? API: Multimedia pronunciation dictionary

  I Heart Quotes API: Quotes and fortunes generator

  iCyte API: Resource and document saving service

  Idescat Catalan and Spanish Indicators API: Economic indicator service

  Idescat Onomastics API API: Catalan name data

  Idescat Rectifications API: Rectifications registry lookup service

  iFixit API: Online repair manual database

  IIAP Servicio Glosario API: Spanish glossary of environmental terms

  ikiMap API: Create Maps From Public and Personal Georeference Information

  IMDBAPI.org API: Unofficial IMDB data retrieval service

  ImpactStory API: Publication influence metrics service

  IndExs API: Index of mycology specimens

  Indian Pincode API: Indian PIN code information service

  Indiana University Knowledge Base API: Tech support reference database

  InfoChimps Datasets API: 2,000+ dataset reference library

  InfoChimps IP Intelligence Demographics API: Census data based on IP address

  Innovative Interfaces: Sierra API: Integrated library system

  Intelius Search API: Public records database search

  Internet Archive API: Non-profit Internet library and historical archive

  Ireland Revenue Customs and Excise API: Irish tax collection office data

  isiZulu API: Zulu-English dictionary

  ISOcat API: Linguistic concept definition registry

  Israel Ministry of Finance Taarif API: Israeli tariff reference service

  iTranslate4.eu API: European language translation service

  JChem ChemAxon API: Chemistry search and reference tool service

  Jigsaw API: Business information and contacts directory

  Kasabi API: Data marketplace

  Kateglo API: Indonesian online dictionary, thesaurus and glossary

  KnowMarkets Address Verification API: Postal and area code lookup services

  Korean Bible Society API: Korean-language Bible

  Kuakes API: International earthquake data

  la Loter�a del Ni�o API: Spanish Lottery Information Lookup

  Language Studio Asia Online API: Online translation service

  Lasso 9 Reference Library API: Lasso 9 reference information retrieval service

  Lawyers.com API: Legal articles archive

  Leafly API: Medicinal marijuana information service

  LER API: Danish underground utility cable information service

  Lexicomp API: Drug and clinical information service

  LexisNexis Academic API: Academic research repository

  Library of Congress SRW API: Information database search

  Library of Congress Subject Headings API: Access to the Library of Congress Subject Headings

  LibraryThing API: Books database and community

  LifeDesks API: Online science and taxonomy community

  LingQ API: language development service

  LinguLab API: Text creation and editing service

  LittleShoot Labs MIME API: File type reference service

  LittleSis API: Database for tracking political and business relationships

  LiveAddress Verification API: US address verification, validation, and geocoding

  LocalSchoolDirectory API: School information and search service

  Lollapalooza API: Music event reference

  London Prayer Times API: Unified Islamic prayer timetable for London

  Longman Dictionary API: English dictionary reference source

  LyricFind API: Music lyrics database

  MacMillan Dictionary API: Online dictionary

  Malaysia Prayer Times API: Muslim prayer times for Malaysia

  Martindale-Hubbell API: Legal directory

  MasterCard Merchant Identifier API: Merchant data lookup service

  MedlinePlus API: Health information service

  Mendeley API: Academic research paper sharing service

  Merriam-Webster Dictionary API: Dictionary and thesaurus products

  MetriDyne API: Real-time measurement accumulates service

  Microsoft MSDN API: Technical reference library

  Mirlyn API: Library catalog and services

  Mnemotechniques Abbreviator API: Abbreviation services

  Morpher API: Russian language reference service

  MovieMeter API: Retrieve film information in Dutch

  MovieZine.se API: Movie database query service

  MTPS Content Service API: Access to Microsoft documentation and related content

  Museum of London API: Access to museum data

  MyAvoxData API: Business entity data

  MyFonts API: Font store

  NADA API: Used car values lookup service

  Naringslex API: Oslo entrepreneurial reference service

  NASA Astrophysics Data System API: Astronomy and physics data service

  Nasa Exoplanet Archive API: Astronomical archive

  National Drug File-Reference Terminology API: Clinical information about medications

  National Library of Medicine ChemSpell API: Chemical reference database

  National Library of Medicine Digital Collections API: Library of medical books and video

  National Library of Medicine DIRLINE API: Medical information resource database

  Nature.com OpenSearch API: Scientific publication search service

  NCSU Libraries CatalogWS API: Library catalog and services

  NCSU Scholarly Publications Repository API: Academic publication information service

  Neil deGrasse Tyson Quotes API: Neil deGrasse Tyson Quotes

  NeuStar Port PS API: Telephone number information automation service

  New York Times Article Search API: New York Times article archives

  New York Times Campaign Finance API: U.S. campaign finance data

  New York Times Congress API: US Congress historical data

  New York Times Districts API: Political districts service

  New York Times Most Popular API: News popularity service

  New York Times Newswire API: All recent New York Times articles in summary

  New York Times NY State Legislature API: NY State legislative member information

  NextBio API: Science data research platform

  Ningbo Institute of Technology SOIP API: Open API for Searching the NIT Information Portal

  Nobel Prize API: Nobel Prize information service

  NoSwearing API: Swear word filter

  NSDL Search API: Online science library

  NTNU IME Faculty API: NTNU University data

  NumberLaundry API: Phone Number Information Service

  Numbers API: Number reference service

  Nursing & Health Survival Guides API: Health and nursing guide series

  Obituarydata.com API: Obituary data archive

  Ockham Spell API: Spelling suggestion service

  OCLC Article Exchange API: Library document sharing service

  OCLC Classify API: Library catalog classification service

  OCLC WMS API: Library collection management services

  Office for National Statistics API: UK neighborhood and census data

  OMA Browser API: Proteins search engine

  OMG API: Computer industry standards database

  OneMusic API: Music metadata collection

  ONKI Ontology and Thesaurus API: Finnish library thesaurus and ontology service

  Open Charge Map API: Electric vehicle charging point database.

  Open Context API: Museum collection resesarch and reference service

  Open Library API: Library data access

  OpenCorporates API: Corporate information database

  OpenDOAR API: Academic research repository

  OReilly Safari API: Book search

  Our Manna Daily Verses API: Daily bible verses

  PastPlace API: Historical data service

  PBS TV Schedules API: TV schedule data service

  Peachpit Visual QuickStart Guides API: Visual QuickStart Guide

  Pearson Brilliant Series API: How-to and reference books

  Pearson Dictionaries API: Dictionary and reference service

  PGXN API: PostgreSQL metadata distribution service

  PhoneVal API: Phone number validation service

  PicketReport Lifestyle API: Neighborhood lifestyle data service

  Pillbox API: Medication identification service

  PilotOutlook API: International airport data

  Pincodr API: Indian pincode search service

  PLoS Search API: Scientific literature search service

  Postcode Anywhere API: UK and international address management software, postcode finder web services and more

  Postcode Anywhere Address Services API: Address capture, lookup and search

  Postcode Anywhere Customer Profiling API: UK population segmentation data service

  Postcode Anywhere Worldwide Business Data API: Business record database

  PostcodePal API: Geographic datasets for the United Kingdom and Crown Dependencies

  Powerhouse Museum Collection API: Online museum collection and datasets

  Pro6PP API: Dutch postcode database services

  Product Life Cycle Support API: Product management service for businesses

  Project Bamboo API: Humanities research support service

  PRONOM API: Electronic records management technical information database

  ProThesaurus API: Protein name thesaurus

  PubChem PUG API: Molecular library database

  PubMLST API: Biological database

  Pulsepoint Real-Time Classifier API: Context definition and classification service

  Pushpin Location Data API: Location and statistical information about places

  Python Package Index API: Python code database

  Qualified Address API: US address verification service

  Questsin API: Thesaurus and answers lookup services

  Quotations Book API: Quotations database

  Quotes Daddy API: Great quotes database

  RadioReference API: Radio station database

  Random House API: Book search and viewing service

  Raphael Research Resource API: Artwork linked data service

  RateBeer API: beer database and rating tool

  Real Estate Transaction Standard API: Real estate information standards reference

  RealEDA Reverse Phone Lookup API: Lookup address and name via phone

  RealSearch Liberty Criminal API: Criminal records search service

  RealSearch Wireless & Cellphone API: Wireless carrier database

  Realtime Register API: Uniform domain name registration service

  Record Setter URDB API: World record reference site

  refbase OpenSearch API: Bibliographic search service

  ReferralCandy API: Customer referral service

  RegExLib API: Database of regular expressions

  Regulations.gov API: U.S. government regulations document repository

  RestFul Web Services Airport API: Airport code reference service

  RestFul Web Services Bible API: Bible verse look-up service

  RestFul Web Services GeoIP API: IP address location service

  RestFul Web Services HCPCS API: Health care procedure code reference service

  RestFul Web Services Postal Code API: International postal code look-up service

  RestFul Web Services UNSPSC API: eCommerce product classification code reference

  RestFul Web Services USA Zip Code API: Zip code location service

  Reverse Australia API: Australian reverse phone lookup service

  RhymeBrain API: Online rhyming dictionary

  Rhyming API: Rhyming dictionary

  RIPE Database API: Internet Registry Database

  Ripe Development API: Local time and zip code information services

  Royal Albert Memorial Museum API: Museum collections data and image database

  RubyGems API: Ruby community gem hosting service

  RxNorm API: Clinical drug vocabularies

  RxTerms API: Drug prescription terminolgies

  Safe Creative API: Free copyright registry

  Sapo Holiday API: Portuguese holiday reference service

  Sapo POI API: Location data service

  Sapo Semantic Lists API: Semantic word lists service

  Sapo Verbetes API: WhoIs query service for public figures

  Scholarly iQ API: Scholarly publication tracking service

  Scholarometer API: Scholar impact rating service

  Science Museum API: British Science Museum data and services

  SciVerse Framework and Content API: Science Reference Research Platform OpenSocial

  Scopus API: Academic citation database

  SDSS CasJobs API: Scientific data and query management system

  SecondHandSongs API: Cover song reference

  SeedFinder API: Cannabis strain information service

  Sem4Tags API: Semantic tagging interpretation service

  Semantics3 API: Product Database

  Sensis Business Search API: Australian business directory search service

  SermonAudio API: Audio sermon library service

  SERP-P API: Philippines demographic data service

  ServiceObjects DOTS Demographics API: Zip code level demographic service

  ServiceObjects DOTS NCOA Live API: U.S. change-of-address (COA) update service

  Sesame Name Resolver API: Astronomical object information service

  Shakespeare API: Shakespearian play quote origin identification service

  SHOUTcast Radio API: Internet radio database service

  SigQuotes API: Random Alistair Young quote generator

  SimpleUPC API: Product information database

  Simply Postcode API: Postcode and address lookup service

  SKGA Golf Hadicap API: Golf handicap in Slovakia

  Skolportalen API: Swedish education resource documentation

  SKOS Thesaurus API: Thesaurus of related concepts

  Socrata Open Data API: Online data sharing service

  Softonic API: Catalog of downloadable software

  SolarGIS API: Solar resources information and calculation services

  SolarPlots API: Sun position tracking service

  Spellchecker.net API: Spelling correction service

  Spire ITIS API: Taxanomic serial number and scientific name database

  Springer API: Scientific journal and books database

  SRC Demographics API: Demographic reference data

  St. Gregorios Church Bible API: Bible verse retrieval service

  Stack Exchange API: Question and answer site network

  STANDS4 Definitions API: Dictionary definition service

  Stanford HighWire API: COUNTER Usage Statistics Service

  State Library of New South Wales API: Internal library website maintenance and fundraising service

  Stochastic IMDb API: Unofficial IMDb service

  StrikeIron Address Verfication API: Global address verification service

  StrikeIron Do Not Call API: Telephone number verification serice

  StrikeIron Foreign Exchange Rates API: Foreign exchange rate information service

  StrikeIron Insider Trading API: Insider trading transaction information

  StrikeIron Lite Web Services API: Financial, census data, phone numbers, and other data

  StrikeIron Phone Number Enhancement API: Adds address and statistical data based on phone number

  StrikeIron Residential Lookup API: Residential directory lookup and validation service

  StrikeIron Reverse Phone Lookup API: Reverse phone lookup services

  StrikeIron Sales Tax Basic API: Sales and use tax data service

  StrikeIron Super Data Pack API: APIs for variety of reference data sources

  StrikeIron Tax Service API: Sales tax reference lookup

  StrikeIron US Addresses API: US address verification service

  StrikeIron US Census API: Census data information service

  StrikeIron Zacks Company Profile API: Corporate profiles web service

  StrikeIron ZIP and Postal Code Info API: ZIP and Postal Code information service

  Styfee API: Internalization and localization services

  SureChemDirect API: Chemistry Patent Data

  Synonyms API: Online thesaurus

  Tariff Analysis Project API: Official utility tariff data service

  Telephony Intelligence Data Services API: Telephony customer data service

  Texas History API: Texas History Resource

  TextRazor API: Text analysis service

  The Alife Database API: Listing of websites related to artificial life

  The Business Model Project API: Business model taxonomy

  The Freedom Registry API: Anti-human trafficking organization collaboration platform

  The Movie DB API: Movie, cast and image database

  The Society of Authors Member Search API: Search for a writer or translator

  Thesaurus API: Multi-languages thesaurus search service

  Thirukkural API: Thirukkural reference service

  Thomas Beyer First Names and Gender API: European names lookup service

  Thomson Reuters Knowledge Direct API: Business information and analytics

  Thomson Reuters Pharma API: Investigational drugs data

  Thomson Reuters Web of Science API: Citation reference index

  ThrustCurve API: Model rocket motor data

  Timetric API: Statistical analysis tools and data

  TimeZoneDb API: Time zone database

  Tixik API: Famous places GPS services

  Tourism New Zealand API: New Zealand tourism information service

  TOXNET API: Toxicology database

  Translated.net API: Professional translation workflow service

  Trends Top API: Company information service

  TurnItin iThenticate API: Plagiarism detection service

  U.S. National Library of Medicine ChemSpell API: Chemical name spell checker and thesaurus

  UC Davis IET API: University directory services

  UK National Archives Discovery API: National archives catalog

  UMBEL API: Semantic structure service

  UN Contrade API: International trade statistics service

  UN Data API: United Nations information service

  Unified Tax API: Sales tax lookup service

  University of Michigan Buildings API: University of Michigan building information

  University of Michigan Courses API: University of Michigan course information

  University of Toronto Libraries API: University of Toronto's library management system

  University of Washington Person API: Personnel directory service

  UNLV Library API: Library catalog

  Unofficial IMDb API: Unofficial search interface for Internet Movie Database (IMDb)

  UPC Database API: UPC lookup service

  UrbanDictionary API: Slang dictionary lookup

  Urbanesia API: Indonesian city lifestyle directory

  USA Today Best-Selling Books API: Best-Selling Books Information Service

  USA Today Book Reviews API: Book review service

  USA Today Census API: U.S. census search service

  USC Schedule of Classes API: University of Southern California class schedule information

  USCG Approved Equipment Listing API: Approved maritime equipment listing

  USCG MARPOL Certificates of Adequacy API: Certified maritime facility database

  USCG Port State Information Exchange API: Marine vessel information service

  USGS Greenness Query API: Geological data service

  USGS United States National Grid Conversion API: Geological data service

  Victoria & Albert Museum API: Museum online collection access

  VINquery API: Motor vehicle identifier decoding service

  Visual DataFlex Country Information API: Country information service

  Visual DataFlex Date Functions API: Multi-language ID code and date name retrieval

  W3 Solutions API: Extended warranty management service

  WareNet CheckWare API: Hardware product database

  WattzOn API: Online Power Usage Tracking

  Wcities API: Travel guide and information service

  WebServiceMart ICD9Code API: IDC9 code look-up service

  WebServiceMart MSPCode API: MSP explanatory code information service

  WebServiceMart MSPFees API: MSP fee information service

  WebServiceMart Phone3T API: Phone number validation service

  WebServiceMart USZip API: Zipcode validation service

  WhitePages.com API: People search service

  WhoSampled API: Music discovery application

  Wiki-Data API: Company/business entity data service

  WikiMatrix API: Wiki search and comparison service

  Wikimeta API: Semantic tagging and content annotation service

  Wikipedia API: Online collaborative encyclopedia

  Wikirandom API: Generate Random Wikipedia Pages

  Wolfram Alpha API: Computational knowledge and search engine

  Wordnik API: Dictionary, spelling, and other word reference

  WordReference API: Multilingual dictionary definition service

  World Bank API: Worldwide indicators, business, and photo databases

  World Bank Climate API: Climate change information portal

  World of Warcraft API: World of Warcraft data service

  World Weather Online City Search API: City lookup service

  World Weather Online Time Zone API: Time zone data service

  World Wide Web of Humanities Wayback API: Archived internet research service

  WorldCat Identities API: Library data access

  WorldCat Search API: Library data access

  WorldCat xISBN API: ISBN and book edition linking service

  Worldwide Lexicon API: Open source, collaborative language translation service

  WSIndex API: Index of informational links on web services

  Xhanch Islamic Get Prayer Time API: Islamic prayer time calculating service

  XigniteHousing API: U.S. housing market statistics

  Yahoo Answers API: Community driven reference service

  Yahoo Spelling Suggestion API: Spelling correction service

  Yellow API: Canadian business listings service

  Yes Broadcast DB API: Radio station search, now-playing, logs and charts

  York University Library API: University library data service

  youcantcall.us API: Reject unwanted phone calls

  YouPage API: Business and local events directory

  ZIP Codes API: Zip code lookup service

  Zip Tax API: Sales tax information by zip code

  ZipCodes API: Simple zip code lookup service

  Zippopotamus API: Zip and postal code service

  ZoomInfo API: Information search services

Be sure to read the next Reference article: IBM's OpenAPI Comment Parser Brings API Reference and Code Development Together