Because the word “lumen” on a projector box is not defined by anything, so a larger number costs nothing to print and cannot be disproved by reading the packaging.
What the large number usually is
The output of the light source, or a value derived from it, before the light passes through the imaging chip, the colour filter and the lens. Every one of those stages absorbs light. The figure is real in the sense that something was measured; it is not the light that reaches your wall.
Why “LED lumens” exists
It rests on a genuine observation — the eye is more sensitive to some wavelengths, and LED sources are heavy in those — and turns it into a multiplier applied to the measured output. There is no standard defining the multiplier, so it varies by manufacturer.
What a maker who states ANSI is telling you
That they are prepared to be compared. On this shelf, the presence of a measured unit correlates with the rest of the specification being honest, which is why these pages treat it as a signal rather than just a number.
How we handle it on this site
Every brightness figure here is written in the unit the manufacturer published, with a note when that unit is not ANSI or ISO. We never convert one into the other, because there is no conversion — only two different things with the same word attached.
This does not replace the manufacturer's own instructions. Every brightness figure, contrast ratio, power rating and load capacity on this page is reported from the manufacturer's own documentation, with its unit written as published, and named as such — none of it is measured here. A brightness figure that is not expressed in ANSI or ISO lumens is reported as the manufacturer expressed it and is never converted, because no conversion exists.
Questions people actually ask
Are these projectors bad?
Not necessarily. A machine producing a few hundred ANSI lumens is genuinely usable in a dark room on a modest image, and that is what many of them are. The problem is the description, not always the product: nothing on the box tells you which of the two numbers describes what you will see.
How can I tell what a projector really produces?
Look for a figure with a unit — ANSI or ISO lumens — anywhere in the listing, including the specification table further down the page. Where a maker states one, it is usually accurate. Where no unit appears at all, this site records that the figure is not published in a measured unit rather than repeating it.
Last reviewed 4 September 2026