Compress video for email
Re-encodes to 720p with a lower audio bitrate, which is what most mail servers need for a video attachment. Files stay on your device.
How this works locally
- You choose a file; the page reads it from your device.
- The matching engine is loaded from fileslimmer.com and runs in a Web Worker.
- The result is written back to a location you choose on this device.
Before or choose files from your device
Original size —
Accepted formats
- Reads
- MP4 · MOV · M4V · WebM
- Writes
- MP4
Estimated memory
Your browser reports only a coarse memory hint, so this figure is an estimate.
| Device profile | Largest video | Longest clip | Multi-threaded fallback |
|---|---|---|---|
| Minimal | 50 MiB | 5 minutes | Single thread |
| Low | 120 MiB | 15 minutes | Single thread |
| Balanced | 300 MiB | 45 minutes | When isolated |
| High | 700 MiB | 120 minutes | When isolated |
Your browser is placed in one of these profiles from the coarse hints it exposes. A file above the limit is refused before it is read, rather than after the tab has run out of memory. On an iPhone or iPad a further ceiling applies whatever the profile — largest video: 50 MiB, longest clip: 5 minutes, multi-threaded fallback: Single thread — because mobile Safari reclaims a tab's memory far more abruptly than the hints can predict.
Limitations
- Re-encoding always costs some quality, and which codecs are available is decided by your browser, not by this page. A clip above the device limit is refused before it can exhaust the tab.
- The target size is what the search aims at, not what the result is promised to be. The search stops at the configured quality floor and reports the smallest file it reached.
- Every frame is decoded and encoded again. On a phone that is the most demanding thing this site can ask of the device, and the browser may throttle it part-way through.
Target size
Best-effort local compression. If the target cannot be reached safely, FileSlimmer returns the smallest acceptable result.