Video Format Converters

Convert video files free in your browser — powered by FFmpeg.wasm. No uploads, no accounts, no watermarks.

MP4 → WebM
MP4 to WebM
Convert MP4 videos to WebM format optimised for the web. Uses VP9 + Opus encoding for best quality.
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WebM → MP4
WebM to MP4
Convert WebM video files to universally compatible MP4. Uses H.264 + AAC for maximum device support.
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MOV → MP4
MOV to MP4
Convert Apple QuickTime .mov files to MP4. Share videos from your iPhone or Mac with anyone.
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AVI → MP4
AVI to MP4
Convert older AVI video files to modern MP4. Dramatically reduces file size while preserving quality.
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MP4 → GIF
MP4 to GIF
Convert video clips to animated GIF. Control frame rate, dimensions, and clip range. Perfect for memes and previews.
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How it works

All video converters on GifWidgets run entirely in your browser using FFmpeg.wasm — a WebAssembly build of the industry-standard FFmpeg library. Your video files are never uploaded to any server. Everything happens locally on your device.

On first use, the converter will download the FFmpeg.wasm core (~30 MB). This is cached by your browser, so subsequent conversions are instant. A modern browser with SharedArrayBuffer support is required (Chrome, Edge, and recent Firefox all work).

Frequently Asked Questions

Are these converters really free?
Yes, completely free. No signup, no watermarks, no file size limits imposed by us (only your device's memory sets the limit).
Is my video uploaded to a server?
No. All conversion happens locally in your browser using WebAssembly. Your files never leave your device.
Which browsers are supported?
Chrome, Edge, and recent Firefox versions support the required SharedArrayBuffer API. Safari has limited support depending on the version.
How large a file can I convert?
There is no hard limit, but very large files (several GB) may be slow or run out of browser memory. For best results, convert files under 2 GB.
What is FFmpeg.wasm?
FFmpeg is the industry-standard open-source tool for video and audio processing. FFmpeg.wasm is a WebAssembly port that runs the same powerful codec library directly inside your browser.