WebM to AVI Converter

How to Convert WebM to AVI Online

1. Upload Your WebM File: Drag and drop or click "+ Add Files" to select WebM clips from your device. Batch uploads are supported, and Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared.
2. Pick a Codec and Quality Preset: Default is H.264 inside AVI, which plays in nearly every Windows tool. For maximum legacy compatibility (DivX/Xvid era media players, set-top DVD players), switch the codec to Xvid or DivX (MPEG-4 Part 2 ASP). Set the Quality Preset to "Very High (Recommended)" or step down to "High"/"Medium" to shrink the file.
3. Resize, Trim, or Cap File Size (Optional): Pick a Preset Resolution (144p through 4320p / 8K), enter a custom Width x Height, or scale by Resolution Percentage. Use Trim → Time Range to keep only the section you need, or switch File Compression to "Specific file size" / "Constant Bitrate" / "Variable Bitrate" / "Constant Quality" to target a precise output size.
4. Convert and Download: Click "Convert." Each AVI lands in your downloads with no watermark, no account, and no upload to a third-party queue.

Why Convert WebM to AVI?

WebM is a Google-backed container built for the open web — it carries VP8, VP9, or AV1 video with Vorbis or Opus audio, and it's natively played by roughly 95% of installed browsers. AVI is older — Microsoft shipped it on November 10, 1992 as part of Video for Windows — but it remains the lingua franca for legacy Windows tools, NLE round-trips, and a long tail of consumer hardware that never learned VP9. Converting trades the modern codec efficiency of WebM for AVI's much wider downstream compatibility.

• Windows Media Player compatibility — WMP doesn't play WebM out of the box; native VP9 support requires installing Microsoft's Web Media Extensions / VP9 Video Extensions from the Store. Re-wrapping into AVI with H.264 or Xvid bypasses the codec-pack dance entirely.
• Older DVD players and set-top boxes — Hardware MPEG-4 ASP decoders (the "DivX Certified" sticker era, roughly 2003-2012) read AVI files with Xvid or DivX video and MP3 audio. WebM is invisible to them.
• NLE and screen-capture round-trips — Older versions of Sony Vegas, Camtasia, and Avid expect AVI inputs. AVI with MJPEG or uncompressed video is also a common intermediate for frame-accurate editing where re-encoding is undesirable.
• Surveillance and machine-vision tooling — Many industrial capture SDKs (Basler, FLIR, OpenCV's VideoWriter default) read and write AVI by default. WebM rarely appears in that pipeline.
• Archival and offline playback on old hardware — A Windows XP era laptop or a Pentium-class kiosk often has DivX/Xvid pre-installed but no VP9 decoder. AVI plays; WebM doesn't.
• Software that hard-requires.avi — Some training datasets, legacy LMS uploaders, and badge-printing kiosks accept .avi only by extension check.

WebM vs AVI — Format Comparison

Codec Quick Guide — Pick the Right Encoder Inside AVI

Frequently Asked Questions

Why is my AVI file much larger than the original WebM?

WebM uses VP9 or AV1, which are roughly a generation ahead of MPEG-4 Part 2 ASP (Xvid/DivX) in compression efficiency. A 50 MB VP9 WebM can easily land at 120-200 MB as an Xvid AVI at visually similar quality. Switching the AVI codec to H.264 in Step 2 closes most of that gap; you'll typically end up within 10-30% of the WebM size at the same Quality Preset.

Will Windows Media Player play the AVI I get out of this?

Yes, as long as you pick a codec WMP already ships with. H.264 in AVI works on Windows 10 and 11 out of the box. Xvid/DivX requires the DivX or K-Lite codec pack on most Windows installs. If you want zero-install playback, leave the default H.264.

Should I pick H.264 or Xvid inside AVI?

H.264 if the target is a modern Windows machine, NLE, or anything from the last ten years — better quality at smaller size. Xvid (or DivX) if you're feeding a 2003-2012 era DVD player with a "DivX Certified" logo, an older car-stereo head unit, or a kiosk that predates H.264 decoding. The AVI container itself doesn't care.

Is there a file size limit on AVI?

The original AVI 1.0 spec from 1992 uses 32-bit indices and caps individual files at 4 GB. The OpenDML / AVI 2.0 extension chains multiple 4 GB RIFF segments to push the practical ceiling to 16 EB. Most modern AVI writers (including this tool) emit OpenDML for files over 4 GB, but some legacy players only read the first RIFF segment. If you're targeting truly old hardware, keep outputs under 4 GB.

Why does my audio sound off or out of sync after conversion?

AVI doesn't reliably store variable-bitrate audio below 32 kHz, and it has no proper timestamp track for VFR (variable frame rate) video. WebM clips captured at variable frame rate — common with screen recorders and MediaRecorder from a browser — sometimes drift when force-fit into AVI's fixed-frame-rate model. If you hit this, re-encode to a constant frame rate before exporting, or use WebM to MP4 instead, since MP4 handles VFR cleanly.

Can I keep subtitles or multiple audio tracks?

No — and that's an AVI container limitation, not a tool limitation. AVI was not designed to carry subtitles, fonts, or chapter markers, and multi-track audio support is patchy across players. If you need soft subs or multiple audio languages, convert WebM to MP4 or MKV instead.

Does AVI support 4K, HDR, or 10-bit color?

Resolution-wise yes — you can put a 3840×2160 H.264 stream inside AVI and it will technically play. But AVI predates HDR metadata standards (HDR10, Dolby Vision), so HDR signal information is lost on conversion. For HDR-preserving workflows stick with MP4 or MKV. 10-bit is supported only by codecs that already support it (H.264 High 10, H.265).

Will the converted AVI play on a Mac?

QuickTime Player on macOS plays H.264-in-AVI fine. Xvid/DivX-in-AVI usually needs VLC or Perian-style codec installs (Perian itself is discontinued). If the target is a Mac user, default H.264 is the safest pick.

What if I want to go the other direction later?

Use AVI to WebM for the reverse trip, or compress AVI if the file is just too big to share. For web playback specifically, WebM or MP4 will give better quality per byte than AVI.