MP4 compressor
Reduce an MP4's file size without sending it anywhere. Choose a target in MB or a percentage of the original and get an MP4 that plays everywhere.
What is a MP4 file?
MP4 (MPEG-4 Part 14) is a container. It usually holds H.264 or H.265 video and AAC audio. The container itself adds almost nothing to the size; the bitrate of the video inside decides it.
Why MP4 files get big, and how this shrinks them
Phone and camera MP4s are recorded at high bitrates (often 10–20 Mbps for 1080p, more for 4K) to leave room for editing. Re-encoding at a bitrate suited to sharing is what makes them smaller.
Tips for MP4
- Keep H.264 if the file is going to someone else; it plays on every device.
- For storage on your own Apple or recent Android device, H.265 or AV1 (if your browser can encode them) gives smaller files at similar quality.
- Drop 60 fps to 30 fps for chat and email; motion still looks smooth and the bitrate goes further.
Need an exact size? Try 20 MB, 25 MB or the bitrate calculator.
Other formats
Questions people ask
How do I reduce MP4 file size without losing quality?
Trim unneeded seconds first (no quality cost), then use a light squeeze or a target that leaves at least 0.05–0.1 bits per pixel. A lower resolution at a sensible bitrate usually looks better than a high resolution starved of bits.
Why is my compressed MP4 not much smaller?
If the original was already encoded efficiently (for example downloaded from a streaming site), there is little left to remove. Pick a smaller target or a lower resolution, and check the real result shown after compression.
Is there a file size limit?
No server limit, since nothing is uploaded. Your device's memory is the limit: computers handle multi-gigabyte files, phones are best under a few hundred megabytes.