Video Compressor failed, stalled, or looks wrong? Troubleshooting
Troubleshoot Video Compressor by codec, container, parameters, memory, and browser while respecting quality and device boundaries.
Do not rename an extension to fake a format
An extension names a container, not a guaranteed video/audio codec. Keep the source and record size, duration, codec, dimensions, browser, and exact error. Never overwrite the only original repeatedly.
The easy-to-miss issue for this tool
For a 200 MB 4K60 clip meant for chat, reduce to 1080p or 720p before choosing medium quality. A 10 MB target can only be estimated, not guaranteed.
Recommended troubleshooting order
- Load a very short, low-resolution known-good sample to confirm the tool starts.
- Check whether duration, video, audio, and dimensions are detected; missing metadata often means damage or an unsupported codec.
- Reduce duration, resolution, frame rate, or simultaneous file count.
- Close heavy tabs, retry in current desktop Chrome/Edge, and keep the page active.
- Reapply the workflow:
- Choose video and record its size, duration, and dimensions.
- Set the quality and audio bitrate exposed by this page.
- Start compression and keep the page active.
- Compare sizes and review picture, sound, and sync completely.
- If it still fails, use desktop FFmpeg or the producing application; do not claim browser support for that codec.
Parameter checks
- Quality / CRF: a higher value is commonly smaller with less detail
- Audio bitrate
- No target-size, resolution, or frame-rate control is currently exposed
Common errors
How do I reach 10 MB?
Lower resolution, quality, and audio bitrate, but content complexity prevents an exact guarantee.
Why is the result larger?
The source may already be efficient and the chosen output settings may be higher.
Is the video uploaded?
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task.
Boundaries that cannot be bypassed
- No guarantee of an exact target size
- Can introduce blocking, banding, blurred text, and audio loss
- Large WASM encodes can be slow or fail from memory pressure
Browser WASM lacks the full performance and codec set of native apps, and long video can take substantial time. A paused progress display does not mean server upload; processing is in the tab, but the browser can terminate it under memory pressure.
Privacy, rights, and open-source licenses
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task. Troubleshooting images and outputs can still contain private, copyrighted, or hidden metadata. The ffmpeg.wasm wrapper is MIT and this release's FFmpeg core is GPL-2.0-or-later; source access and license notices must not be removed.