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Server-sent events

EventSource is an interface that exposes events from a server to the browser as they occur. It allows developers to push data to the browser as it happens, in real-time.

Last updated on : 2026-02-09

Browser Versions

IE

Edge

Firefox

Chrome

Safari

Opera

5.5 - 11

12 - 18

79 - 144

2 - 5

6 - 150

4 - 5

6 - 147

3.2 - 4

5.1 - 26.3

9.5 - 10

11.6 - 125

Fully Supported

Partially

No Support

Browser Compatibility

Server-sent events on IE is not supported on any IE versions.

Server-sent events on Edge is fully supported on 79-144, and not supported on 12-18 Edge versions.

Server-sent events on Firefox is fully supported on 6-150, and not supported on 2-5 Firefox versions.

Server-sent events on Chrome is fully supported on 6-147, and not supported on 4-5 Chrome versions.

Server-sent events on Safari is fully supported on 5.1-26.3, and not supported on 3.2-4 Safari versions.

Server-sent events on Opera is fully supported on 11.6-125 and partially supported on 9.5-10 Opera versions.

Server-sent events on Safari on iOS is fully supported on 4.2-26.3, and not supported on 3.2-3.2 Safari on iOS versions.

Server-sent events on Android Browser is fully supported on 4.4-144, and not supported on 2.3-4 Android Browser versions.

Server-sent events on Opera Mobile is fully supported on 11.5-80 and partially supported on 10-11 Opera Mobile versions.

Server-sent events on Chrome for Android is fully supported on all Chrome for Android versions.

Server-sent events on Firefox for Android is fully supported on all Firefox for Android versions.

Server-sent events on Samsung Internet is fully supported on all Samsung Internet versions.

Browser Support for Server-sent events

Server-sent events on Chrome

Server-sent events on Safari

Server-sent events on Firefox

Server-sent events on Internet Explorer

Server-sent events on Opera

Server-sent events on Edge

References

Data sourced from

92

High

Overall Browser Compatibility Score

Note:Server-sent events shows a browser compatibility score of 92. This is a collective score out of 100 to represent browser support of a web technology. The higher this score is, the greater is the browser compatibility. The browser compatibility score is not a 100% reflection for every browser and the web technology support. However, it does give you an estimate on how much you should rely on a particular web technology in terms of browser compatibility.

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