Converts AVI files to WebM format — legacy video compatibility to web-optimized video. All conversion happens locally in your browser with no file size limits.
Runs on FFmpeg
Content reviewed October 2026 · About Toolzum
Convert WEBM video files to AVI format directly in your browser. 100% free, private — your files never leave your device.
Convert MKV video files to WEBM format directly in your browser. 100% free, private — your files never leave your device.
Convert MP4 video files to AVI format directly in your browser. 100% free, private — your files never leave your device.
Convert MKV video files to MP4 format directly in your browser. 100% free, private — your files never leave your device.
Convert MP4 video files to MOV format directly in your browser. 100% free, private — your files never leave your device.
AVI (Audio Video Interleave) uses uncompressed or lossy encoding and is best for legacy video compatibility — older software, embedded systems, and archival playback. WebM (WebM Video) uses lossy compressed encoding and excels at web-optimized video — streaming, embedded players, and HTML5 video tags with fast loading. Converting between them lets you take advantage of each format's strengths — for example, using a compressed format for sharing and a lossless format for editing. All conversion happens locally in your browser with no file size limits.
The converter typically uses VP8 for faster encoding. VP9 may be available for higher quality at smaller file sizes, but encoding is slower.
WEBM encoding introduces small quality differences depending on bitrate. Choose high quality settings for best visual fidelity.
Yes. <video src='video.webm'> works in all modern browsers. WEBM is the recommended format for HTML5 video alongside MP4.
Yes. All conversion runs in your browser using FFmpeg. No video files are uploaded.
Video to MP3 Converter
Extracts the audio track from uploaded video files (MP4, MOV, AVI, WebM) and encodes it as a high-quality MP3 file. Free to start with no signup.
Crop Video
Crop the visual area of your MP4 or WebM video directly in the browser with 9:16, 1:1, 16:9 presets or custom dimensions with X/Y offsets. Free to start with no signup.
Video Compressor
Reduces MP4, MOV, and WebM video file sizes with a configurable CRF 20–40 slider (default 28, libx264 fast preset), plus a GIF mode with color-palette control. Videos never leave your device — compression runs locally in your browser with FFmpeg WASM.
Video to GIF
Convert MP4/WebM to GIF animations. Videos up to 250MB. Videos never leave your device — compression and conversion run locally in your browser with FFmpeg WASM.
Subtitle Translator
Translate pasted SRT or VTT subtitle text into 9 languages (Spanish, French, German, Japanese, Chinese, Hindi, Portuguese, Russian, Arabic) while preserving every timestamp — AI-powered with your own API key, text never stored.
Video Watermark Adder
Burn text watermarks into a video with 5 position presets (bottom-right default, fixed 24px white on semi-transparent black box). Brand one clip at a time — local FFmpeg work, unlimited saves.