Video compressor

What this tool does

The compressor reads the file with this browser’s media engine, scales the long edge to 1280px if needed, and re-encodes with the encoders this tab exposes. MP4 uses H.264; WebM uses VP9, or VP8 if VP9 is missing. Each format is tried at a medium setting first, then a lower setting only if the file is still not smaller. The smallest output under the original size is recommended. Audio is kept when this browser can encode AAC or Opus; otherwise that candidate is silent and labelled. Results live in this tab only.

How to use it

1. Drop one clip under 80 MB and 90 seconds. Encoding starts immediately.
2. Wait. A minute of video can take a minute of work. Cancel if you need the tab back.
3. Compare original and encoded previews, then download the recommended file or another listed format.

Privacy

This tool processes files and text locally in your browser. Your content is not uploaded or stored by this site.

ConvertPass does not include your input in analytics, URLs, or error reports. Encoding: This browser’s decoder and encoder. Long edge scaled to 1280px. Metadata tags are not copied.. Limit: 1 file, 80 MB, 90 seconds (80.00 MB).

Limitations

• This is not an unrestricted transcode farm. One file, 80 MB, 90 seconds, 1280px long edge.
• Formats offered are whatever this tab can encode. Safari, Firefox, and Chrome differ. Missing formats are omitted, not faked.
• HEVC, ProRes, and other edit codecs encode only if this browser can decode them first. Many cannot.
• HDR is refused. Audio may be dropped if AAC or Opus cannot be encoded here. Already-compact files may not get smaller.
• Results are held in tab memory only. Reload, reset, or closing the tab discards them. There is no database.

Example

clip.mov 1920×1080, 18 s, 24 MB

clip-compressed.mp4 ~6 MB at 1280×720, auto-selected if smaller than the original

Troubleshooting

No formats appear, or encoding fails immediately

This browser has no usable video encoder, or cannot decode the source. Try a current Chrome or Edge with an H.264 MP4.

The file did not get smaller

The original was already compact, or the encoder could not beat it at a watchable setting. Download a listed conversion anyway, or compress further in an editor.

The download has no sound

This browser could not encode AAC or Opus for that container. The candidate is labelled silent. Try Chrome for MP4 with AAC, or keep the original audio in an editor.

FAQ

Is this a desktop encoder running in the tab?

No. ConvertPass uses the encoder this browser already exposes. That is why Chrome, Safari, and Firefox offer different formats, and why a minute of video can take a minute of work on your device.

Do you store my video?

No. There is no account and no server-side video store. Blobs stay in this tab until you download, reset, or reload.

Why 90 seconds and 1280px?

In-tab encode is CPU, GPU, battery, and memory. Those caps keep a laptop usable. Longer or larger jobs belong in an editor.

Which format should I download?

The recommended row is the smallest file that beat the original. H.264 MP4 still plays in the most places. WebM can be smaller when this browser’s VP9 encoder is available.

Can I convert HEVC or ProRes here?

Only if this browser can decode that track. Many cannot. Export an SDR H.264 file from your editor, then compress that.