Comparison of WebSocket implementations

The WebSocket protocol is implemented in different web browsers, web servers, and run-time environments and libraries acting as clients or servers. The following is a table of different features of notable WebSocket implementations.

	Client (library)	Server (library)	Version compared	Protocol (spec) version support	Protocol test report	License	Implementation: language, environment	API: language, environment	Self-hosted server	Text message support	Binary message support	API message-based	API frame-based	API streaming input-output	Flow-control framework	Automatic pongs for pings	Automatic heartbeat pings	Manual pings-pongs	Frame size limit
Google Chrome 15[1]	Yes	No	15.0.874.8 12 Sep 2011	8 (10)		Complex	C++, WebKit	JavaScript, HTML5	No	Yes	Yes	Yes	No	No, No	No	Yes	No	No	≥ 16 MB (memory-limited?)
Google Chrome 16[1]	Yes	No	16.0.912 13 Dec 2011	13 (17/RFC 6455)		Complex	C++, WebKit	JavaScript, HTML5	No	Yes	Yes	Yes	No	No, No	No	Yes	No	No	≥ 16 MB (memory-limited?)
Mozilla Firefox 7[2]	Yes	No	7 beta 12 Sep 2011	8 (10)		MPL, GPL, LGPL	C++, Necko	JavaScript, HTML5	No	Yes	No	Yes	No	No, No	No	Yes	No	No	< 16 MB
Mozilla Firefox 11[2]	Yes	No	11.0 13 Mar 2012	13 (17/RFC 6455)		MPL, GPL, LGPL	C++, Necko	JavaScript, HTML5	No	Yes	Yes	Yes	No	No, No	No	Yes	No	No	< 2 GB (memory-limited?)
Achex WS[3]	Yes	Yes	2.17 17 June 2014	RFC 6455		Commercial	C++	C++, JavaScript	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	No	Yes	2^16
Kaazing WebSocket Gateway[4]	Yes	Yes	5.0 Dec 2014	RFC 6455		APL2 (Community Edition), commercial (Enterprise Edition)	Java, JMS	JavaScript, Flash/Flex, Silverlight, Objective-C & iOS, Java, Java & Android, .NET, Xamarin	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No	memory-limited, configurable
Lightstreamer[5]	Yes	Yes	7.1.1 27 May 2020	RFC 6455		Commercial, freeware	Java	JavaScript, Flash/Flex, Silverlight, iOS, macOS, tvOS, watchOS, Java, J2ME, Android, .NET Standard	Yes	Yes	No	Yes	No	No	Yes	Yes	Yes	No	Data driven, configurable
MigratoryData[6]	Yes	Yes	5.0.28 23 Aug 2019	RFC 6455		Commercial	Java	JavaScript, iOS, Android, Java, C++, .NET, PHP, Node.js, Python, Ruby	Yes	Yes	No	Yes	No	No, No	Yes	Yes	Yes	No	2^63, configurable
noPoll[7]	Yes	Yes	0.3.2 28 aug 2015	RFC 6455		LGPL 2.1	ANSI C	ANSI C	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	memory-limited, configurable
POCO C++ Libraries[8]	Yes	Yes	1.4.6 23 Sep 2014	RFC 6455		Boost	C++, POCO C++ Libraries	C++	Yes	Yes	Yes	No	Yes	Yes	No	No	No	Yes	memory-limited, configurable
PowerWebSockets[9]	Yes	Yes	15.176.5188 26 Jun 2015	RFC 6455	Test report[10]	Commercial	.NET	.NET Framework, .NET Compact Framework, Xamarin. iOS, Xamarin.Android, Windows Phone, Silverlight, Mono	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	memory-limited, configurable
Push Technology Diffusion[11]	Yes	Yes	4.6.1	RFC 6455		Commercial	Java	JavaScript, Flash/Flex, Silverlight, Objective-C & iOS, Java, Java & Android, .NET, Java J2ME & BlackBerry, C/C++, Node.js	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes[12]	Yes[12]	No	memory-limited, configurable
QtWebSockets[13]	Yes	Yes	1.0 12 Nov 2013	RFC 6455		LGPL	C++, Qt	Qt	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	memory-limited, configurable
RingSocket[14]	No	Yes	1.0 13 Sep 2019	RFC 6455		MIT	C	C	Yes	Yes	Yes	Yes	No	No	Yes	Yes	No	No	unlimited/configurable
Resin[15]	No	Yes	4.026 29 Feb 2012	RFC 6455		GPL, commercial	Java, C	Java		Yes	Yes	Yes	No	Yes	No	Yes	No	No	memory-limited, configurable
WebSocketListener[16]	No	Yes	2.1.3 24 Nov 2014	RFC 6455		MIT	.NET, Mono	.NET, Mono	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No	Configurable
Wt[17]	No	Yes	3.2.0 30 Nov 2011	0,7,8,13 (17)	[? Report]	GPL, commercial	C++, Boost Asio	C++		Yes	Yes	No	No	No	Yes	Yes	Yes	No	memory-limited, configurable
XSockets.NET[18]	Yes	Yes	5.*	RFC 6455		Commercial	.NET	Server-languages: Windows (.NET), Unix-Linux (Mono) Client-languages: JavaScript, .NET, Mono	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	memory-limited, configurable
RIWA Gateway[19]	Yes	Yes	2.01	RFC 6455		Commercial	Java	Java, Android, iOS, JavaScript	Yes	Yes	Yes	Yes	No	Yes	No	Yes	No	No	memory-limited, configurable
µWebSockets[20]	No	Yes	v0.14.0 28 Mar 2017	RFC 6455	Test report[21]	Apache License 2.0	C++, epoll, Libuv, Boost Asio	C++, JavaScript, Node.js	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	memory-limited, configurable
Boost.Beast[22]	Yes	Yes	94 30 July 2017	RFC 6455	Test report[23]	Boost	C++, Boost Asio	C++	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	unlimited (packets streamed to user code), permessage-deflate also unlimited (chunked)
libwebsockets[24]	Yes	Yes	2.4 16 Oct 2017	RFC 6455 + RFC 7692	Test report[25]	LGPL2 + SLE	C, libuv, libev, libevent, poll, external poll loop integration, OpenSSL, mbedTLS	C, HTML5, JavaScript	Yes	Yes	Yes	Yes	Yes	Yes, yes	Yes	Yes	Yes	Yes	unlimited (packets streamed to user code), permessage-deflate also unlimited (chunked)
websocket++[26]	Yes	Yes	0.7.0 22 Feb, 2016	RFC 6455		BSD	C++11	C++11	?	?	?	?	?	?	?	?	?	?	?
facil.io[27]	Yes	Yes	0.7.1 18 May 2019	RFC 6455		MIT	C	C	Yes	Yes	Yes	Yes	Yes	Yes, yes	Yes	Yes	Yes	Yes	configurable client to server limits. unlimited (chunked) server to client.
oatpp-websocket[28]	Yes	Yes	1.1.0 25 May 2020	RFC 6455		Apache License 2.0	C++11, Oat++	C++11, Oat++	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	No	Yes	unlimited (packets streamed to user code)

Notes

1. Chromium website
2. Necko website
3. Achex WS website
4. Kaazing website
5. Lightstreamer website
6. MigratoryData website
7. noPoll website
8. POCO C++ Libraries documentation
9. PowerWebSockets website
10. PowerWebSockets Autobahn|Testsuite report
11. Push Technology website
12. Pings and heartbeats are defined in the Diffusion protocol layer
13. QtWebSockets website
14. RingSocket (GitHub)
15. Caucho website
16. WebSocketListener website
17. wt website
18. XSockets.NET website
19. RIWA website
20. µWebSockets (GitHub)
21. µWebSockets Autobahn|Testsuite report
22. Boost.Beast (GitHub)
23. Beast.WebSocket Autobahn|Testsuite report
24. libwebsockets.org website
25. libwebsockets.org lws Autobahn|Testsuite report
26. websocket++ website
27. facil.io website
28. oatpp.io website