Web 2.0 API Directory

http://www.programmableweb.com/apis/directory/1?&pagesize=All

API	Description	Category	Mashups
Google Maps	Mapping services	Mapping	1296
Flickr	Photo sharing service	Photos	297
Amazon eCommerce	Online retailer	Shopping	215
YouTube	Video sharing and search	Video	209
411Sync	SMS, WAP, and email messaging	Messaging	118
eBay	Online auction marketplace	Shopping	116
Microsoft Virtual Earth	Mapping services	Mapping	115
Yahoo Maps	Mapping services	Mapping	108
Google Search	Search services	Search	95
del.icio.us	Social bookmarking	Bookmarks	94
Yahoo Search	Search services	Search	93
Yahoo Geocoding	Geocoding services	Mapping	68
Technorati	Blog search services	Blog Search	50
Google Homepage	Portal gadgets	Widgets	44
Facebook	Social networking service	Community	40
Last.fm	Music playlist management	Music	40
Google Ajax Search	Web search components	Search	38
Yahoo Local Search	Local search service	Search	37
Yahoo Image Search	Image search services	Search	36
GeoNames	Geographic name and postal code lookup	Mapping	32
Amazon S3	Online storage services	Storage	29
Shopping.com	Online retail shopping	Shopping	28
Google Calendar	Calendar service	Calendar	26
FeedBurner	Blog promotion tracking service	Blogging	25
Google AdSense	Advertising management	Advertising	25
Twitter	Community site	Community	25
Windows Live Search	Internet search	Search	25
Google Base	Platform for structure and semi-structured data	Shopping	24
Upcoming.org	Collaborative event calendar	Events	24
geocoder	Geocoding services for US	Mapping	23
Skype	Internet communication	Telephony	23
Amazon EC2	Elastic Compute Cloud virtual hosting	Internet	22
Yahoo Term Extraction	Contextual search service	Search	21
Google AdWords	Search advertising	Advertising	20
Trynt	Term extraction service	Other	20
Eventful	Events discovery and demand	Events	19
BBC	Multimedia archive database	Media Management	18
Digg	Community driven news links and ratings	News	18
Google Ajax Feeds	Access RSS and Atom feeds with JavaScript	Feeds	17
MSN Messenger	Chat and messaging	Chat	17
Yahoo Video Search	Video search	Video	17
Yahoo Shopping	Shopping services	Shopping	15
Yahoo Traffic	Traffic data and routing	Other	15
hostip.info	IP lookup	Internet	14
Rhapsody	Online music services	Music	14
Zillow	Real estate pricing and valuations	Real Estate	14
Blogger	Blogging services	Blogging	13
imageLoop	Animated slideshow service	Photos	13
Yahoo Answers	Community driven reference service	Reference	13
Google Desktop	Desktop search and gadgets	Search	12
Netvibes	Personalized home page with widgets	Widgets	12
Commission Junction	Online affiliate programs	Shopping	11
HotOrNot	Dating rating site	Dating	11
Multimap	Global online mapping service	Mapping	11
ClearForest Semantic Web Services1	Natural language processing tools	News	10
Salesforce.com	CRM services	Enterprise	10
Yahoo Map Image	Map image creation service	Mapping	10
Zvents	Local events search and community	Events	10
Amazon A9 OpenSearch	Search services	Search	9
Google Mashup Editor	Mashup creation tool extensions API	Tools	9
indeed	Job search services	Job Search	9
PayPal	Online payments	Payment	9
Yahoo Widgets	Desktop widgets	Widgets	9
Dapper	Service for API creation	Internet	8
Vast	Structured web search	Search	8
Yahoo Related Suggestions	Search suggestion service	Search	8
AOL Video	Video search service	Video	7
Basecamp	Project collaboration service	Project Management	7
BigTribe	Location based advertising	Mapping	7
CNET	Shopping services	Shopping	7
Findory	Personalized news aggregation	News	7
geocoder.ca	Geocoding services for Canada	Mapping	7
Google Custom Search	Google custom search management	Search	7
MusicBrainz	Music metadata community service	Music	7
NOAA Weather Service	Weather forecast database	Weather	7
Panoramio	photo upload site with organizer and geolocation	Photos	7
Poly9 FreeEarth	3D mapping service	Mapping	7
Revver	Video services	Video	7
SecondLife	Virtual world	Other	7
Trulia	Real estate search	Real Estate	7
WeatherBug	Weather forecast services	Weather	7
Yahoo My Web Search	Personalized search services	Search	7
Yahoo Travel	Online travel services	Travel	7
Zazzle	On-demand product creation service	Shopping	7
23	Photo sharing service	Photos	6
Amazon Mechanical Turk	Request services of humans	Other	6
AOL Instant Messenger	Instant messaging chat service	Chat	6
FedEx	Package shipping	Shipping	6
Google Chart	Chart creation service	Other	6
Grouper Video	Video sharing service	Media Management	6
Kayak	Travel search service	Travel	6
Ontok	Geocode any US address	Mapping	6
RapLeaf	Portable reputation system	Community	6
Adobe on AIR Bus Tour	Services to track Adobe AIR product launch	Other	5
Alexa Web Search	Web Search Engine	Search	5
Cafe Press	Customized retail product service	Shopping	5
Google Checkout	Shopping cart services	Shopping	5
Google Picasa	Photo management and sharing service	Photos	5
Ma.gnolia	Social bookmarking service	Bookmarks	5
Map24 AJAX API	Mapping services	Mapping	5
Riya	Photo search	Photos	5
UrbanDictionary	Slang dictionary lookup	Reference	5
Windows Live Contacts Control	Contacts control	PIM	5
Windows Live Expo	Online classifieds service	Shopping	5
30 Boxes	Calendar service	Calendar	4
Alexa Web Information Service	Web site information and traffic data	Search	4
Clickatell	SMS Messaging services	Messaging	4
Follow The Money	Database of US campaign contributions	Government	4
FUTEF Wikipedia API	Third party Wikipedia web service	Reference	4
Google Spreadsheets	Online spreadsheets	Office	4
Google Talk	Chat application	Chat	4
MapQuest	Online mapping service	Mapping	4
Microsoft MapPoint	Mapping services	Mapping	4
Microsoft Silverlight Streaming	Streaming application management service	Other	4
Raw Sugar	Web directory service	Other	4
SharedBook	On-demand reverse publishing system	Other	4
Smugmug	Photo sharing service	Photos	4
SNOCAP	Digital music marketplace	Music	4
Sunlight Labs	US Congress database service	Government	4
UPS	Package shipping	Shipping	4
US Postal Service	Package shipping and postage	Shipping	4
Weather Channel	Weather forecast data	Weather	4
Windows Live Gadgets	Online gadgets service	Widgets	4
Windows Live Spaces	Blog services	Blogging	4
Yahoo Audio Search	Music search services	Media Search	4
Yahoo Mail	Web based email system	Email	4
Yelp	Local user reviews and city guides	Recommendations	4
ZeeMaps	Embedded maps and international geocoding	Mapping	4
Alexa Top Sites	Web site traffic rankings	Internet	3
Aonaware Dictionary	Dictionary lookup service	Reference	3
Backpack	Online information manager	Office	3
Bloglines	Online feed aggregator	Feeds	3
Box.net	Online file storage	Storage	3
BT Web21C	Communications services APIs	Other	3
Compete	Internet web site metrics and analytics	Internet	3
FormSpring	Online forms service	Internet	3
Fotolia	Royalty free stock photos	Photos	3
GeoIQ	Geospatial analysis and heat mapping service	Mapping	3
Jaiku	Social messaging service	Messaging	3
LiveVideo	Video repository and user community	Video	3
Moreover	News delivery	News	3
NASA	Satellite mapping images	Mapping	3
Naver	Korean search engine	Search	3
Nestoria	UK real estate listings	Real Estate	3
NewsCloud	Social news service	News	3
NewsGator	Feed aggregation	Feeds	3
Ning	Service creation playground	Other	3
OpenLayers	Mapping API abstraction layer	Mapping	3
Shadows	Social bookmarking and community	Bookmarks	3
SplogSpot	Database of spam blogs	Blog Search	3
SpringWidgets	Widget platform	Widgets	3
Syndic8	News feed aggregation services	Feeds	3
Windows Sidebar Gadgets	Desktop gadgets	Widgets	3
Yahoo Ads	Online ad management	Advertising	3
43Things	Social goal setting	Other	2
Amazon Flexible Payments Service	eCommerce payments service	Payment	2
Amazon Queue Service	Internet-based queuing service	Other	2
AOL Open Auth	Authentication services	Security	2
AOL Open Mail	Email services	Email	2
bLaugh Comics	Online comic strip	Other	2
Blinksale	Online invoicing services	Financial	2
Blue Dot	Content sharing community	Bookmarks	2
DataUnison eBay Research	eBay pricing and sales trend data	Shopping	2
Digital Podcast	Podcast search	Music	2
EditGrid	Online spreadsheet	Office	2
ESV Bible Lookup	Bible lookup service	Other	2
Garmin MotionBased	GPS services and mapping	Mapping	2
Gigablast	Search service	Search	2
GlobeXplorer	Mapping services	Mapping	2
Google Client Authentication	Account authentication for installed applications	Security	2
Google Notebook	Online notebook service	Utility	2
InnerGears Weather by City	US Weather forecasts by city	Weather	2
LinkShare	Affiliate marketing network	Shopping	2
LiveJournal	Blogging software	Blogging	2
Microsoft start.com	Portal service	Widgets	2
Mobivity	SMS marketing messaging service	Messaging	2
MusicMobs	Social music service	Music	2
NCBI Entrez	Life sciences search services	Medical	2
Ontok Wikipedia	Encyclopedia data access	Wiki	2
Pageflakes	Personalized start page and widgets	Widgets	2
PhishTank	Community site for tracking phishing	Security	2
Plaxo	Address book management	PIM	2
Plazes	Location discovery service	Mapping	2
SeeqPod	Music recommendation service	Music	2
Shopzilla	Comparison shopping service	Shopping	2
Snipshot	Online photo editing service	Photos	2
Sparklines	Graph generation service	Other	2
SpokenBuzz	Voice services portal	Telephony	2
StrikeIron Global SMS Pro	SMS messaging services	Messaging	2
StrikeIron Super Data Pack	APIs for variety of reference data sources	Reference	2
StrikeIron US Census	Census data information service	Reference	2
TagTooga	Tag based Internet directory	Tagging	2
Topicalizer	Document analysis service	Other	2
Veoh	Virtual television and video network	Video	2
WebAIM	Web based instant messaging	Chat	2
Weblogs	Blog ping service	Blogging	2
WebShots	Photo sharing service	Photos	2
WebThumb	Thumbnail image generation service	Internet	2
Windows Live Data	Service for users to control data access	Security	2
Yahoo BBauth	Browser based authentication service	Security	2
Yahoo Messenger	Instant messaging	Chat	2
Yahoo Site Explorer	Web site analysis service	Internet	2
AIM Phoneline	Voice Over IP Internet telephony services	Telephony	1
Alexa Site Thumbnail	Thumbnail images of web site home pages	Internet	1
AMEE	Avoiding Mass Extinctions Engine - CO2 calculations	Other	1
Authorize.Net	Internet based payment gateway services	Shopping	1
Autodesk Freewheel	CAD model viewing, printing and collaboration	Other	1
buySAFE	E-commerce trust network	Security	1
Buzznet	Photo sharing	Photos	1
City and State by Zip Code	Address lookup service	Reference	1
Clicky	Web site analytics	Internet	1
Creative Commons	Licensing engine integration	Other	1
DabbleDB	Online database service	Database	1
Daylife	Online News Service	News	1
DBpedia	Structured query interface to Wikipedia	Wiki	1
deCarta	Location-based services	Mapping	1
Democracy In Action	eAdvocacy services for nonprofits	Government	1
EarthTools	Web services for geographical information	Mapping	1
EasyUtil	Recommendation service	Recommendations	1
eSideWalk	Community networking site	Other	1
ExactTarget	Email delivery services	Email	1
FedSpending.org	Database of US government spending	Government	1
FeedMap	Blog geo-coding	Mapping	1
GetMapping	Aerial photography and mapping service	Mapping	1
Google Apps Email Migration	Migrate existing email systems to Google Apps	Email	1
Google Code Search	Code search service	Search	1
Google Safe Browsing	Security service to verify URLs	Security	1
Google Single SignOn	Authentication for Google Apps	Security	1
Google Translate	Language translation service	Utility	1
Google Web Authentication	Account authentication proxy for web-based applications	Security	1
Gruvr	Live music and concert information	Music	1
hon.jp	Japanese eBook metadata service	Catalog	1
iGoogle Themes	Google homepage design service	Other	1
Interfax	Fax services	Fax	1
Internet Archive	Non-profit Internet library	Internet	1
JamBase	Live music and concert information	Music	1
Jots	Social bookmarking	Bookmarks	1
JotSpot	Wiki-style collaboration tools	Wiki	1
Kuler	Adobe web service for creating color themes	Other	1
Lat49	Geo-targeted advertising for online maps	Advertising	1
Library of Congress SRW	Information database search	Reference	1
LinkedIn	Business social networking platform	Community	1
Living Stones	Bible lookup service	Other	1
Macromedia News Aggregator	Data access service	News	1
MetaCarta	Location and geotagging services	Mapping	1
Microsoft MSDN	Technical reference library	Reference	1
MyBlogLog	Social footprint sharing service	Community	1
MySpace	Social networking service	Community	1
NewsIsFree	Online news aggregation	News	1
Omnidrive	Online storage services	Storage	1
Open Patent Services	European Patent Office web services	Government	1
OpenDOAR	Academic research repository	Reference	1
OpenStreetMap	The Free Wiki World Map	Mapping	1
Orb	Digital media remote access and management	Media Management	1
Pingdom	Web site monitoring and reporting services	Internet	1
Pixagogo	Online photo services	Photos	1
PriceGrabber	Comparison shopping service	Shopping	1
PriceRunner	Shopping comparision engine	Shopping	1
Prodigem	File sharing via BitTorrent	File Sharing	1
Prosper	Peer-to-peer lending network	Financial	1
PubSub	Blog and feed search	Blog Search	1
Pushpin	Mapping service	Mapping	1
QuarkRank	Consumer reviews service	Shopping	1
Rakuten	Japanese shopping web service	Shopping	1
Remember the Milk	Personal information management	PIM	1
Rentometer	Realestate pricing services	Real Estate	1
Rrove	Social Bookmarking for Places Create & Share Maps	Bookmarks	1
ShutterPoint	Stock photography service	Photos	1
Simpy	Social bookmarking	Bookmarks	1
Skyhook Wireless	Wifi positioning services	Other	1
SlideShare	Presentation sharing community	Office	1
SmashFly	Job board posting service	Job Search	1
stikkit	Little sticky notes that think	Utility	1
StrikeIron Reverse Phone Lookup	Reverse phone lookup services	Reference	1
StrikeIron Tax Service	Sales tax reference lookup	Other	1
tagthe.net	Tag recommendation service	Tagging	1
Tailrank	Blog search and news aggregation service	Blog Search	1
Textamerica	Moblogs	Messaging	1
TheyWorkForYou	Track the UK Parliament	Government	1
TradeSports	Online sports betting exchange	Other	1
Tunelog	Music metadata management	Music	1
Tutorials Garden	Online tutorials service	Other	1
Twittervision	Location based data for the Twitter service	Messaging	1
TypeKey	Authentication Framework	Security	1
TypePad	Blog management	Blogging	1
UPC Database	UPC lookup service	Shopping	1
US Yellow Pages	US yellow pages telephone directory	Reference	1
USGS Elevation Query Service	Determine elevation based on latitude and longitude	Mapping	1
We Feel Fine	Art project that harvests feelings from blogs	Other	1
WebPurify	Profanity filtering service	Other	1
Where2GetIt SlippyMap	Online mapping service	Mapping	1
Windows Live Admin Center	Web site administration services	Internet	1
Windows Live Contacts	Contacts database	PIM	1
Windows Live ID Web Authentication	Web based authentication service	Security	1
Windows Live Spaces Photo Control	Programmable widget for blog photos	Photos	1
Yahoo Music Engine	Desktop music player	Music	1
Yahoo Search Marketing	Search advertising platform	Advertising	1
yourminis	Widget Platform	Widgets	1
Zixxo	Online coupons	Shopping	1
Zoho	Online office suite	Office	1
ZoomIn	New Zealand mapping service	Mapping	1
ZoomInfo	Information search services	Reference	1