How many lumen does a LED car headlight bulb really have?

H11 H8 H16 LED Headlight Bulb 6SMD 9-32V No Fan 40W 4000LM White or Yellow

In order to be able to differentiate between the fake Lumen rating of LED car headlight and the actual Lumen rating of LED car headlight, it is important to understand what Lumen is. The Lumen is the SI unit of the luminous flux and it is often denoted as lm. Luminous flux is the measure of the total amount of visible light released by a source. The amount of Lumen is considered to be the level of brightness of the LED car headlight bulb.