Step 1: Supply your WebM files using the button above or by haul and lay.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Get your converted MP4 files.
WebM to MP4 Conversion FAQ
What does the WEBM to MP4 converter do?
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It transcodes a WEBM video into the MP4 container. Resolution, frame rate, and aspect ratio are preserved by default — useful when you need a different format for a target player without quality loss.
Will resolution and frame rate be preserved in the MP4?
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Yes. WEBM → MP4 keeps resolution, frame rate, and aspect ratio unchanged by default. To change them, use the Resize or Speed tool on the result.
Is the WEBM to MP4 conversion reversible?
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You can convert the MP4 back to WEBM on this site. If either format involved is lossy, the round-trip is not bit-perfect even though it is visually or audibly close.
Will the converted MP4 be a different size than the WEBM?
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Modern codecs compress better, so MP4 from a legacy WEBM is typically 30-60% smaller at equivalent quality. Conversions in the opposite direction can grow the file.
Is there a file-size limit when converting WEBM to MP4?
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Anonymous uploads are capped at a generous default; signed-in free accounts get a higher cap, and Pro accounts have no per-file limit. Browser memory is usually the practical constraint long before our server-side limits kick in.
Can I batch-convert several WEBM files to MP4 at once?
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Yes. Drop or pick multiple WEBM files in one upload — the converter processes them in parallel and returns a ZIP of the MP4 results. There is no need to repeat the upload step per file.
What happens to my WEBM files after the conversion?
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Uploaded files and MP4 outputs are auto-deleted after a short retention window. We do not inspect, share, or train on user files. Direct download links are time-limited and tied to your session.
Will my MP4 play on phones, tablets, and TVs?
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Yes — MP4 uses modern codecs that play natively on iOS, Android, Smart TVs, game consoles, and every modern browser.
Do I need to install software to convert WEBM to MP4?
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No. The converter runs entirely in your browser plus our cloud — no plugin, no install, no admin rights. It works on Windows, macOS, Linux, ChromeOS, iOS, and Android.
Do I need an account to convert WEBM to MP4?
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No. WEBM to MP4 conversion is free and works without an account. Signing in unlocks higher file-size caps, batch history, and API access.
Is there an API for WEBM to MP4 conversion?
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Yes. Every conversion this site offers is also exposed via a JSON API — see /api/ for endpoints, authentication, and rate limits. WEBM to MP4 is one of the supported pairs.
What if my WEBM fails to convert to MP4?
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Failures are usually caused by corrupted source files or unsupported WEBM variants. Re-export from the original app and try again; if it still fails, the contact page forwards the file to support so we can diagnose.