Compress an MP4 without uploading it.

Choose an MP4, set the size or visual-quality goal, and compare the measured result before saving.

Keep the original videoProcess a selected local file and create a separate verified result.

Quick answer

Use target size for a hard upload limit, quality for a visual trade-off, or resolution when the destination does not need the original dimensions.

How to do it

01
Choose the local video
Select the video from your computer. The extension reads only the file you choose.
02
Set the output
Choose the size, quality and resolution that matches the destination.
03
Compare and save
Preview the result, compare its measured size and save the new copy only after it passes verification.

MP4 is a container. Its size comes mainly from video bitrate over time, plus audio; changing only the filename cannot reduce it.

Processing runs locally in Chrome. Video bytes, frames, thumbnails, filenames and paths are not uploaded for conversion.

Start with Balanced quality. Lower resolution before forcing a long or detailed clip into an unrealistically small target.

Preview the result, compare its measured size and save the new copy only after it passes verification.

An already efficient MP4 may not shrink much without a visible quality trade-off.
Input decoding and output encoding depend on the source codec, Chrome version and device capabilities.
The result can be larger or smaller depending on duration, motion, audio, resolution and codec efficiency.

Can I compress MP4 without changing the format?

Yes. Choose MP4 as the output and adjust quality, resolution or target size.

Is the video uploaded?

No. The selected video is processed locally in Chrome.

Is the original changed?

No. The extension creates a separate output and leaves the original untouched.

Keep the original, compare the new file and save only the result you want.