Step 1: Supply your MP4 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 WebM files.
MP4 to WebM Conversion FAQ
What does the MP4 to WEBM converter do?
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It transcodes a MP4 video into the WEBM 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 WEBM?
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Yes. MP4 → WEBM keeps resolution, frame rate, and aspect ratio unchanged by default. To change them, use the Resize or Speed tool on the result.
Is the MP4 to WEBM conversion reversible?
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You can convert the WEBM back to MP4 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 WEBM be a different size than the MP4?
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Modern codecs compress better, so WEBM from a legacy MP4 is typically 30-60% smaller at equivalent quality. Conversions in the opposite direction can grow the file.
Is WEBM worth targeting for a video on a web page?
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For a page you control, yes. WEBM was built for exactly that job — it plays inline in every current browser with no plugin, no licence fee and no patent exposure, which is why it became the default for embedded and background video. Away from the browser it is the weaker choice: editing software, phone galleries and televisions largely ignore it, so it is a delivery format rather than a storage one. Keep the master in something else and publish this. WebM plays natively in every modern browser with no plugin, no licence fee and no patent exposure, which makes it the default for web-embedded video.
Both MP4 and WEBM are modern containers — which should I actually keep?
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Keep whichever matches where the file is going, because neither is better in the abstract. One of these two is built for playback compatibility and the other for holding everything a file might contain, and they trade against each other exactly along that line. The pragmatic answer for most libraries is to archive in the feature-rich container and export to the compatible one on demand. MP4 is the safest possible delivery target — every phone, browser, console, editor and Smart TV built in the last decade plays it without extra software.
Is there a file-size limit when converting MP4 to WEBM?
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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 MP4 files to WEBM at once?
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Yes. Drop or pick multiple MP4 files in one upload — the converter processes them in parallel and returns a ZIP of the WEBM results. There is no need to repeat the upload step per file.
What happens to my MP4 files after the conversion?
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Uploaded files and WEBM 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 WEBM play on phones, tablets, and TVs?
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Yes — WEBM 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 MP4 to WEBM?
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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 MP4 to WEBM?
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No. MP4 to WEBM conversion is free and works without an account. Signing in unlocks higher file-size caps, batch history, and API access.
