Editing jQuery().fn.attr vs jQuery().fn.prop vs jQuery().fn.data vs jQuery().data This edit will create a new revision. Your details (optional) Name Email (won’t be displayed; might be used for Gravatar) URL Test case details Title * Published (uncheck if you want to fiddle around before making the page public) Description (in case you feel further explanation is needed)(Markdown syntax is allowed) Testing different ways of setting/reading data-* attributes using jQuery, especially after noticing that Twitter's Bootstrap uses $.fn.attr('data-X') instead of $.fn.data('X')... Using the Browserscope table (click on the Browserscope logo above the charts) would probably allow for more useful filtering of the data, and thus ease comparing the speed of the different write+read tests versus the different read-only tests. Thanks for helping! Are you a spammer? (just answer the question) Preparation code Preparation code HTML (this will be inserted in the <body> of a valid HTML5 document in standards mode) (useful when testing DOM operations or including libraries) <script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script> <div id="rw"></div><div id="ro" data-text="readonly"></div> <script> // 'el-lo read-write element var $rw = $('#rw'); var rw = $rw[0]; // 'el-lo read-only element var $ro = $('#ro'); var ro = $ro[0]; var get; // access holder, so that dead stores aren't so easily culled off. // Store only 19 strings to test. // In real code, there usually are not very many // unique keys that get accessed and mutated. // It needs to be odd so that after counter%limit loops, // the attr/prop/data accessors return values. // This also shakes up the key/value pairs. var counter, limit = 19; var rnd = []; // Pre-create all strings unique, just to make sure nothing funny happens. for (var i = 0; i < limit; i++) { rnd[i] = 'X-' + i + '-' + Math.floor(Math.random() * 1001); } function nextKey() { return rnd[counter++ % limit]; } function nextVal() { return rnd[counter++ % limit]; } </script> Include JavaScript libraries as follows: <script src="//cdn.ext/library.js"></script> Define setup for all tests (variables, functions, arrays or other objects that will be used in the tests) (runs before each clocked test loop, outside of the timed code region) (e.g. define local test variables, reset global variables, clear canvas, etc.) (see FAQ) counter = 0; Define teardown for all tests (runs after each clocked test loop, outside of the timed code region) (see FAQ) Code snippets to compare Test 1 Title Async (check if this is an asynchronous test) Code $rw.attr('data-' + nextKey(), nextVal()); get = $rw.attr('data-' + nextKey()); Test 2 Title Async (check if this is an asynchronous test) Code $rw.prop('data-' + nextKey(), nextVal()); get = $rw.prop('data-' + nextKey()); Test 3 Title Async (check if this is an asynchronous test) Code $rw.data(nextKey(), nextVal()); get = $rw.data(nextKey()); Test 4 Title Async (check if this is an asynchronous test) Code $.data(rw, nextKey(), nextVal()); get = $.data(rw, nextKey()); Test 5 Title Async (check if this is an asynchronous test) Code $.data($rw, nextKey(), nextVal()); get = $.data($rw, nextKey()); Test 6 Title Async (check if this is an asynchronous test) Code get = $ro.attr('data-string'); Test 7 Title Async (check if this is an asynchronous test) Code get = $ro.prop('data-string'); Test 8 Title Async (check if this is an asynchronous test) Code get = $ro.data('string'); Test 9 Title Async (check if this is an asynchronous test) Code get = $.data(ro, 'string'); Test 10 Title Async (check if this is an asynchronous test) Code get = $.data($ro, 'string');