About

This tool converts inefficient GIF (Graphics Interchange Format) animations into modern, high-efficiency WebM video files. GIFs store every frame as a full image, leading to massive file sizes. WebM uses temporal compression (storing only changes between frames), often resulting in 80% to 95% smaller files.

The converter utilizes the browser's native ImageDecoder and MediaRecorder APIs to decode the GIF frames and re-encode them as a video stream pixel-perfectly. This process happens entirely on your device.

Formulas

The efficiency of the conversion is measured by the reduction ratio:

Efficiency = (1 - Size_videoSize_gif) × 100%

Where Size represents the file size in bytes.

Reference Data

Format	Compression	Alpha Channel	Color Depth	Typical Usage
GIF	Lossless (LZW)	1-bit (Binary)	8-bit (256 colors)	Simple animations, Memes
WebM	Lossy (VP8/VP9)	Supported	24-bit + Alpha	HTML5 Video, Streaming
MP4	Lossy (H.264)	No (usually)	24-bit	Universal Video
APNG	Lossless	8-bit	24-bit	High-quality Stickers

Frequently Asked Questions

GIF is a legacy format (1989) that is extremely inefficient for video-like content. WebM provides much smaller file sizes, better color depth (no 256-color limit), and allows for player controls (pause, seek).

Yes. However, the output video format (WebM) support for transparency depends on the player. Most browsers support transparency in WebM, but some desktop players might display a black background.

No. This tool uses the WebCodecs API inside your browser. The conversion happens locally on your CPU/GPU.

GIF frame delays are stored in centiseconds (1/100s). Video encoders work with precise timestamps. Small rounding errors in the GIF specification may result in millisecond-level differences.