Convert WEBM to MP4 online

Re-encode a short SDR WebM clip as MP4 with H.264 video and optional AAC audio.

Automatic deletion

InputWEBMOutputMP4

Step 1 of 3 · Files

Expires in 24 h

Files
Format
Result

Expires in 24 h

Select WEBM files

From your phone, computer, or drag them here

· 50.0 MB per file · up to 1

From your phone, computer, or drag them here. · 50.0 MB per file · up to 1

The listed formats are accepted. Each file's structure is validated before conversion.

What will I receive?

WEBM to MP4

The result is MP4 with H.264 video and optional AAC audio, up to 720p/30 fps. Subtitles, attachments and capture metadata are removed; this is not a lossless remux.

Conversion limits

What limits apply?

One video up to 50 MB and 2 minutes, SDR, maximum 4K/60 fps. Output up to 720p/30 fps. HDR and multiple video or audio tracks are not supported. Subtitles are removed.

Input and output expire automatically after the period shown in the converter. Download your result before then.

Practical guide

Convert WEBM to MP4: limits and checks

It is a compatibility output for players that require H.264 video and AAC audio. This guide explains what changes from WEBM to MP4 and what to inspect before publishing the result.

When WEBM to MP4 is appropriate

It is a compatibility output for players that require H.264 video and AAC audio.

What the WEBM input may contain

One SDR WEBM up to 50 MB, two minutes and 4K/60 is accepted, with one video and at most one audio stream.

How the MP4 output is built

MP4 is capped at 1280×720 and 30 fps, uses H.264/AAC and drops subtitles, attachments, chapters and metadata.

How to compare WEBM and MP4

Play the start, middle and end; check sync, framing and actual compatibility. Keep the WEBM because transcoding is lossy and does not retain every stream.

Also compare MP4 to WEBM and MOV to MP4 when the destination needs a different trade-off.

Frequently asked questions

Which WEBM input does this conversion accept?