Not lossless

Compress without wrecking the picture

“Without losing quality” is search language. True lossless will not hit 20 MB. What you can do is spend the bit budget on the current frame size, then drop to 720p only when the math says 1080p would look worse.

Try in the browserDesktop app
8 MBHard cap10 MBDiscord20 MBDefault25 MBEmail

Output about 20 MB · MP4 · files stay on this device


Why this size

“Without losing quality” is search language. True lossless will not hit 20 MB. What you can do is spend the bit budget on the current frame size, then drop to 720p only when the math says 1080p would look worse.

How it is compressed

VideoToSize estimates bits per second from the target size and the duration, minus audio. If that rate is too low for the current resolution, it steps down. The desktop app uses two-pass x264 so the file lands at or under the stamp.

What happens to quality

You will lose information. Short clips hide it. Long 4K does not. Preview, then keep the original. We will not write “lossless” on a 20 MB file.


Questions

Is this lossless?

No. If anyone says a 20 MB 4K export is lossless, they are selling.

CRF or target size?

Target size. CRF is a quality knob, not a Discord limit.