Compress video
MP4, MOV and WebM. Smaller files that still look right. Nothing is uploaded.
Saving needs the page opened in claude.ai. You can still compress and compare here.
Files
No files yet.
Private
Files are processed on your device and never uploaded.
Free
No sign-up, no watermark, no file limits.
Checked
Every result is compared with the original before you save it.
Video compression that checks its own work
Most online video compressors pick one bitrate for everything, so some videos come out bloated and others blocky. Aivdo measures instead of guessing.
For each codec your device supports, an agent encodes short samples from the start, middle and end of your video at different bitrates, decodes them and compares frames to the original with SSIM. The lowest bitrate that clears your fidelity target wins, and the full video is encoded with it. If nothing smaller can look as good, your original is kept.
Encoding uses your device's hardware video engine through WebCodecs, so it is fast and your videos are never uploaded.
- Drop MP4, MOV, WebM or MKV files above.
- Choose a compression level and, if needed, "H.264 only" for maximum compatibility.
- Save the compressed MP4.
FAQ
Which video formats are supported?
MP4, MOV, WebM, MKV and M4V input. Output is MP4 using H.264, HEVC or AV1.
Which browsers can compress video?
Chrome, Edge and Safari 17 or newer, using the WebCodecs API.
Are my files uploaded?
No. Compression runs in your browser, so your files never leave your device. Aivdo only counts anonymous usage (country, file type and sizes). File names and contents are never sent.
Which compression level should I pick?
Recommended keeps files looking the same and suits almost everything. Extreme and Maximum make files much smaller but lower the quality, which is handy for email limits. Maximum tries several settings on PDFs and keeps the smallest valid file.
Which browsers work?
Images and PDFs work in every modern browser. Video needs Chrome, Edge or Safari 17 or newer.
Is there a size limit?
No fixed limit. Very large videos (over about 1–2 GB) can run out of browser memory, so split those first.
What if a file can't get smaller?
Aivdo keeps the original and tells you. You never get back a bigger file.