User Agent String explained :
 Firefox 99.0 | |
|---|---|
| Mozilla | MozillaProductSlice. Claims to be a Mozilla based user agent, which is only true for Gecko browsers like Firefox and Netscape. For all other user agents it means 'Mozilla-compatible'. In modern browsers, this is only used for historical reasons. It has no real meaning anymore |
| 5.0 | Mozilla version |
| Windows NT 10.0 | Operating System:  Windows 10 |
| Win64 | (Win32 for 64-Bit-Windows) API implemented on 64-bit platforms of the Windows architecture - currently AMD64 and IA64 |
| x64 | 64-bit windows version |
| rv:99.0 | CVS Branch Tag The version of Gecko being used in the browser |
| Gecko | Gecko engine inside |
| 20100101 | Build Date: the date the browser was built |
| Firefox | Name : Firefox |
| 99.0 | Firefox version |
| Last visit: | 2025.10.19 11:22 |
All Firefox user agent strings | |