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a browser detector
JavaScript Makefile
branch: master

Merge pull request #88 from hansman/master

Detect chrome book user agent.
latest commit 7446eebc4a
@ded authored


A Browser detector. Because sometimes, there is no other way, and not even good modern browsers always provide good feature detection mechanisms.

bowser ci

So... it works like this:

if (bowser.msie && bowser.version <= 6) {
  alert('Hello China');

Flags set for detected Browsers[Engines]

  • chrome[webkit]
  • firefox[gecko]
  • msie
  • msedge
  • Android native browser as android[webkit]
  • iOS native browser as ios[webkit]
  • opera[webkit if >12]
  • phantomjs[webkit]
  • safari[webkit]
  • seamonkey[gecko]
  • BlackBerry native browser as blackberry[webkit]
  • WebOS native browser as webos[webkit]
  • Amazon Kindle browser as silk[webkit]
  • Bada browser as bada[webkit]
  • Tizen browser as tizen[webkit]
  • Sailfish browser as sailfish[gecko]

For all detected browsers the browser version is set in the version field.

Flags set for detected mobile Operating Systems

  • android
  • Windows Phone as windowsphone
  • ios (iphone/ipad/ipod)
  • blackberry
  • firefoxos
  • webos (touchpad)
  • bada
  • tizen
  • sailfish

Android, iOS, Windows Phone, WebOS, Bada, and Tizen will all report the OS version number if it is contained in the UA string in the osversion field. iOS is always reported as ios and additionally as iphone/ipad/ipod, whichever one matches best. If WebOS device is an HP TouchPad the flag touchpad is additionally set.

All detected mobile OSes are additionally flagged mobile, if they are not powering a tablet device. If a tablet device is detected, the flag tablet is set instead.


Safari, Chrome and some other minor browsers will report that they have webkit engines, Firefox and Seamonkey will report that they have gecko engines.

if (bowser.webkit) {
  // do stuff with safari & chrome & opera & android & blackberry & webos & silk

Ender Support


"dependencies": {
  "bowser": "x.x.x"
if (require('bowser').chrome) {
  alert('Hello Silicon Valley')

Graded Browser Support

One useful feature of Bowser is that aside from checking one browser from another -- it will keep up to date with Yahoo's Graded Browser Support chart, giving you access to each grade on the bowser object

if (bowser.a) {
  // support full feature set
else if (bowser.c) {
  // serve degraded version
else {
  // unsupported (bowser.x)


If you'd like to contribute a change to bowser, modify the files in src/, then run the following (you'll need node + npm installed):

$ npm install
$ make test

Please do not check-in the built files bowser.js and bowser.min.js in pull requests.

Adding tests

See the list in src/useragents.js with example user agents and their expected bowser object.

Whenever you add support for new browsers or notice a bug / mismatch, please update the list and check if all tests are still passing.

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