Test ex unit with Ahem font On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS parseFloat(computedStyleDiv("word-spacing", "1ex")) is within 0.05 of 12.8 PASS parseFloat(computedStyleRect("word-spacing", "1ex")) is within 0.05 of 12.8 PASS successfullyParsed is true TEST COMPLETE