The value gets stored either as a matrix or a matrix3d, depending on whether or not the z value was set. Assuming no other transformations, for a 2D matrix, X and Y are the last two values. For a 3D matrix, X, Y, Z, 1 are the last four digits.

You could use a regular expression to get the values:

function getTransform(el) {

    var results = $(el).css('-webkit-transform').match(/matrix(?:(3d)(d+(?:, d+)*(?:, (d+))(?:, (d+))(?:, (d+)), d+)|(d+(?:, d+)*(?:, (d+))(?:, (d+))))/)



    if(!results) return [0, 0, 0];

    if(results[1] == '3d') return results.slice(2,5);



    results.push(0);

    return results.slice(5, 8);

}