Fast browser fingerprint library. Written in pure JavaScript, no dependencies. By default uses Murmur hashing and returns a 32bit integer number. Hashing function can be easily replaced. Feather weight: only 843 bytes when gzipped.
Fingerprinting is a technique, outlined in the research by Electronic Frontier Foundation, of anonymously identifying a web browser with accuracy of up to 94%.
A browser is queried for its agent string, screen color depth, language, installed plugins with supported mime types, timezone offset and other capabilities, such as local storage and session storage. Then these values are passed through a hashing function to produce a fingerprint that gives weak guarantees of uniqueness.
No cookies are stored to identify a browser.
It's worth noting that a mobile share of browsers is much more uniform, so fingerprinting should be used only as a supplementary identifying mechanism there.
Read more or discuss on reddit
If you're on Rails, add this to your Gemfile
gem 'fingerprintjs-rails'
and
bundle install
After that you can add the file to sprockets:
//= require fingerprint
Otherwise, just copy the file to your js directory.
var fingerprint = new Fingerprint().get();
var hasher = new function(value, seed){ return value.length % seed; }
var fingerprint = new Fingerprint(hasher).get();
Running specs manually is just opening the specs/test_runner.html
Running specs from the command line or in CI requires phantomjs in your PATH
cd specs
phantomjs lib/phantom-jasmine/run_jasmine_test.coffee test_runner.html
The example is in run.sh
file.
To minify the file I recommend using uglifyjs(requires node.js) If you don't have it installed, install it with:
npm -g install uglify-js
Then run the minification with:
uglifyjs fingerprint.js > fingerprint.min.js -mc
-mc
tells uglifier to (m)angle and (c)ompress the input code.
If you don't have node.js installed on your machine, you can create a minified version of the library with online services, such as Google Closure compiler
This code is MIT licenced:
Copyright (c) 2013 Valentin Vasilyev
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.