Compress WebM Video

The tool re-encodes the video stream using the codec and quality settings you choose. Re-encoding means every frame is decoded from the original and then encoded again at a lower target bitrate. This reduces the amount of data stored per second of video. The output is always a WebM file, matching the input container. The audio stream is also re-encoded to fit the new file.

The maximum upload size is 1 GB per file. You can process up to 10 videos per day per IP address. That daily limit is shared across video compression and video conversion on the same network. The counter resets at midnight UTC. If you reach the limit, you will need to wait until the next reset before uploading again.

AV1 generally produces the smallest files at a given quality level because it uses more advanced compression algorithms than VP9 or VP8. However, AV1 encoding takes longer. VP9 is the default and offers a good balance between output size and encoding time. VP8 is older and typically produces larger files than VP9 at equivalent quality settings. For the absolute smallest WebM, try AV1 at 60 to 65 percent quality.

The quality slider sets the target bitrate as a percentage of the original. At 70 percent (the default), most videos look close to the original while achieving a meaningful size reduction. Settings below 50 percent will produce visible compression artifacts, especially in motion-heavy scenes. Settings above 85 percent produce very little size reduction. For web embeds or background loops, 55 to 65 percent is often sufficient. For content where detail matters, stay at 70 percent or above.

The download link expires 300 seconds (5 minutes) after the compression finishes. After that, the file is no longer accessible from the server. This is by design: files are not stored long-term. Download your compressed WebM as soon as the result screen appears. If the link expires before you download, you will need to upload and compress the file again.

Compression re-encodes the video at a lower bitrate while keeping the same container format. You put in a WebM and get back a smaller WebM. Conversion changes the container or codec to a different format entirely, such as turning a WebM into an MP4. Both operations re-encode the video stream, but compression targets size reduction within the same format, while conversion targets format compatibility. If you need to change the format, use the video converter instead.

Yes. Resolution reduction lowers the number of pixels per frame, which directly reduces the amount of data the encoder needs to store. Going from 1080p to 720p, for example, reduces the pixel count by more than half. Combined with a lower quality setting, resolution reduction is one of the most effective ways to minimize file size. Use it when the video will be displayed at a smaller size anyway, such as a thumbnail loop or a mobile-targeted embed.

Uploaded files and compressed outputs are stored temporarily on the server and deleted automatically after the session ends. The download link expires after 300 seconds, at which point the output file is no longer accessible. No account is created and no files are retained for longer than needed to complete the compression and deliver the result. You can review the full data handling policy on the privacy page .

Yes. The tool accepts any valid WebM file regardless of the codec it was originally encoded with. You can then choose to output it with VP9, AV1, H.264, H.265, or VP8. Note that H.264 and H.265 are not native to the WebM container specification, so browser support for WebM files using those codecs is inconsistent. For broadest compatibility in web contexts, VP9 or AV1 are the recommended output codecs.

If the original file was already compressed at a low bitrate, re-encoding it at a similar or lower quality setting may not reduce the size much, and in some cases can slightly increase it due to encoding overhead. This happens because the encoder has to work with a source that already has compression artifacts, making efficient re-compression harder. In those cases, lowering the quality slider further or reducing the resolution will produce a more noticeable size reduction.

Yes. The tool runs in a browser and processing happens on the server, not on your device. That means it works on phones and tablets regardless of their processing power. Upload speeds on mobile networks will affect how long it takes to send the file to the server, but the encoding itself is not limited by your device hardware. The progress bar updates in real time so you can track encoding from any browser.

Yes, the tool is free. No account or payment is required. The only limit is 10 videos per IP address per day, shared across video compression and conversion. This limit exists because server-side video encoding is computationally intensive. If you need to process more than 10 videos in a single day, you would need to wait until the daily counter resets at midnight UTC.