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Make browser recordings easier to share as MP4
WebM is common in browser recordings. This tool re-encodes to H.264 video with optional AAC audio for delivery, editing and sharing. The original file stays intact; changing an extension is never used as conversion.
WebM to MP4 features
- Sequential batch: up to 5 videos, with per-file progress, errors and downloads.
- Frame and audio: source size or long-side limit, quality, frame-rate limit and AAC/silent output.
- Verified output: inspect the MP4 container and AVC/AAC sample entries before preview and download.
How to convert WebM to MP4
Choose or drop WebM files. Select a queue item to preview its source.
Set size, quality, frame rate and audio. Check target dimensions and estimated size.
Start conversion and keep the page visible. Check MP4 picture and audio, then download each result.
WebM to MP4 use cases
Organize browser recordings, product demos, tutorials and ad deliveries. MP4 / H.264 improves interoperability; check each platform’s size, duration, bitrate and audio requirements separately.
WebM to MP4 FAQ
Is this renaming or real conversion?
WebM is decoded and encoded as H.264 MP4, with AAC when retaining audio. Actual MP4 sample entries are verified. WebM or other codecs are not disguised as MP4. Re-encoding is lossy.
Why can some browsers not convert or keep audio?
The browser needs WebM decoding, Canvas capture and H.264 MP4 encoding. Keeping audio also needs media-element capture and AAC encoding. Missing support is reported; try silent mode or another supported browser.
Why does conversion take about the video duration? Can I background it?
This records and encodes at playback speed and depends on device load; hardware acceleration is not guaranteed. Keep the page visible. Backgrounding stops the current task and keeps completed files. Cancel anytime; incomplete files are not downloadable results.
What are the size and quality limits?
Up to 5 files, 200 MB total input; each ≤5 min, 16 MP and 8192px per side. Output long side ≤1920px, ≤100 MB each and ≤150 MB total. Use a size limit for large sources. Odd sides add up to 1px black padding without stretching. Quality and size depend on source and encoder.
Are videos uploaded or saved automatically?
Videos are decoded and converted through local Blob URLs without uploading or persistence. Changing settings clears old results; refreshing or leaving clears the queue. Download needed files before removing or closing.