Get the hash for the HEAD of your branch in 12 lines of code. Purely client-side; no dependencies

getCurrentHead.html

Current hash for master: <span id="currentHash"></span>
<script>
/** 
* This displays the commit hash for the HEAD of your chosen Git branch.
* It helps you stay on the same page with other team members during 
* development. If their hash matches yours, your branches are in the same state.
* 
* This is useful for web projects that don't follow a standard versioning process.
* If you have an automated process for keeping track of versions, this code may 
* complement it. 
*
* @param {String} branch The Git branch you care about (e.g. master or develop)
* @param {Object} el DOM element where the result should be displayed.
*/ 
(function (branch, el) {
	var xmlRequestObj = new XMLHttpRequest; 

	xmlRequestObj.onreadystatechange = function () {
		if (xmlRequestObj.readyState == 4) {
			window.addEventListener('load', function () {
				el.innerHTML = xmlRequestObj.responseText.slice(0, 10); 
			}, false); 
		}
	};

	xmlRequestObj.open('GET', '.git/refs/heads/' + branch); 
	xmlRequestObj.send(); 
})('master', document.getElementById('currentHash')); 
</script>