Convert GIF to WebM Online
Convert animated GIFs to WebM. Up to 95% smaller. Free, in your browser, no file uploads.
.gif · up to 100 MB
What you can do
GIF to WebM: up to 95% smaller, same visual appearance
Web performance
Replace heavy GIFs with WebM VP9 for faster web pages and better Core Web Vitals scores.
Discord and Telegram
Upload animations to Discord and create Telegram video stickers with compact WebM files.
100% private
Your GIF never leaves your device. FFmpeg.wasm processes everything locally in WebAssembly.
Extreme size reduction
A 10 MB GIF can become a 500 KB WebM. No perceptible visual loss.
How it works
Three steps, no hassle
Upload your animated GIF
Drag or select your .gif file — meme, sticker, web animation. Up to 50 MB, no signup.
GIF to WebM VP9
FFmpeg.wasm converts GIF frames to VP9 video in a WebM container with extreme compression. A 5 MB GIF can become a 200 KB WebM with the same visual quality.
Download your WebM
Video ready for HTML5 video tag, Discord, Telegram, or web embedding — up to 95% smaller than the original GIF.
FAQ
Got questions?
GIF (Graphics Interchange Format) was invented by CompuServe in 1987, when the goal was to transmit simple images over 1200-baud modems. Its compression algorithm is LZW (Lempel-Ziv-Welch), designed for text and limited-palette graphics compression. LZW compresses repeated horizontal lines well, but is terribly inefficient for the motion patterns typical in animations: each frame is stored almost in full, without leveraging temporal similarity between consecutive frames. WebM with VP9, published by Google in June 2013, uses inter-frame compression: it analyzes the difference between consecutive frames and only encodes what changes, using block motion prediction with block sizes from 4x4 to 64x64 pixels. The result is dramatic: a typical animated GIF with a white background and moving text or figure can be compressed 10x-20x in WebM. Giphy, the world's largest GIF platform with 700 million daily users per their 2020 data, uses WebM internally for storage because literal GIFs would be economically unviable at that scale.
Yes, with the correct HTML5 pattern. GIFs loop by default thanks to a Netscape application extension block (NETSCAPE2.0) that specifies the repeat count (0 = infinite loop). In WebM and the HTML5 video tag, looping is achieved with the loop attribute: <video autoplay loop muted playsinline src='animation.webm'></video>. This pattern is exactly what Google recommends for replacing GIFs with video in its web performance guide (web.dev). The muted attribute is necessary because browsers block automatic playback of video with audio; playsinline prevents iOS from forcing full-screen. Convertir.ai generates WebM with parameters optimized for this use case.
Discord accepts WebM for videos and clips in chat, but Discord stickers are static PNG or APNG (Animated PNG). For uploading an animation to Discord as a message, WebM works perfectly and takes much less space than the equivalent GIF — Discord itself converts uploaded GIFs to WebM internally for serving. Telegram uses TGS (Telegram Sticker, based on Lottie JSON) for animated stickers, and WebM for video stickers (introduced in Telegram 8.0, September 2021). Telegram video stickers are exactly WebM VP9 with transparent background (alpha channel in VP9), maximum 512x512 pixels and maximum 3 seconds duration. Converting a GIF to WebM is the first step to creating a Telegram video sticker.
WebM cannot be used in an HTML <img> tag. The <img> tag supports static formats (JPG, PNG, WebP, AVIF) and some animated formats (GIF, APNG, animated WebP), but not WebM video. To use WebM on the web as a GIF replacement, the correct tag is <video>: <video autoplay loop muted playsinline><source src='animation.webm' type='video/webm'><source src='animation.mp4' type='video/mp4'></video>. The MP4 fallback ensures compatibility with older iOS Safari and other browsers. This pattern is recommended by Google in its Core Web Vitals guide for optimizing LCP (Largest Contentful Paint) and reducing page weight.
The reduction depends on animation content, but it's typically dramatic. GIFs with full-screen motion or moving backgrounds: 90-95% reduction (a 10 MB GIF becomes 500 KB-1 MB in WebM). GIFs with a small figure on a static background: 70-85% reduction. Simple animated text GIFs: 85-92% reduction. Google's 2015 benchmarks (published on the Chromium blog) showed that replacing animated GIFs with WebM on typical web pages reduced animation asset weight by 85% on average. Firefox and the W3C Performance Working Group have included 'don't use animated GIFs' in their web performance guides since 2018. Giphy reported in 2016 that serving WebM instead of GIF reduced their bandwidth by 60% for the same visual content.
Yes, VP9 supports transparency through an alpha channel (VP9 Profile 1 and 3 include support for pixel formats with alpha). However, most basic converters don't generate WebM with alpha. Transparent GIF uses a color index designated as transparent in its 256-color palette. To replicate this in WebM, the VP9 encoder must be configured with yuva420p (YUV with alpha channel) instead of yuv420p. Convertir.ai detects whether the original GIF has transparency and generates VP9 WebM with alpha channel when necessary, preserving transparent backgrounds for correct use on web pages with colored backgrounds or background images.
Convert GIF to WebM: up to 95% smaller for web performance, Discord, and Telegram
Converting GIF to WebM is the web performance optimization with the highest impact-to-effort ratio available in 2025. GIF (Graphics Interchange Format) was invented by Steve Wilhite at CompuServe on June 15, 1987, originally to transmit color images over CompuServe networks at 1200-2400 baud — speeds where a 320x200 pixel image took minutes to download. Its compression algorithm, LZW (Lempel-Ziv-Welch, patented by Unisys until 2003), was designed for text and simple vector graphics data compression, not animation. Animation in GIF was added as a secondary feature in the GIF89a specification (July 31, 1989), and infinite looping capability came even later, via Netscape Communications Corporation's unofficial extension in 1995 (NETSCAPE2.0 block). The result is an animation format with a fundamental compression inefficiency: LZW only compresses within each individual frame, without leveraging temporal redundancy between consecutive frames. If you have a 100-frame GIF where the background doesn't change, GIF stores the background 100 times. VP9, the modern video codec developed by Google from VP8 (acquired with On2 Technologies in February 2010) and published in June 2013, uses inter-frame motion prediction: it detects that the background is identical between frames and encodes it only once, storing only motion vectors and prediction residuals for what actually changes. The compression difference is staggering: factors of 10x to 20x in typical animations are common.
The impact of GIF to WebM conversion on real web performance is quantifiable and significant. Google published in its Chromium blog in 2015 an analysis of real web pages where animated GIFs represented a disproportionate share of total page weight: on pages with high-quality GIFs, animation assets could represent 40-70% of total transfer weight. Converting to WebM reduced this component by 85% on average, with extreme cases of up to 97%. Google's Core Web Vitals, the set of user experience metrics that directly impact search engine rankings since May 2021, implicitly penalize large GIFs: heavy GIFs trigger a high LCP (Largest Contentful Paint) if they are the largest element on screen, increase CLS (Cumulative Layout Shift) if loaded asynchronously, and impact FID (First Input Delay) / INP (Interaction to Next Paint) due to the CPU load of GIF rendering. Giphy, with over 700 million daily users per their 2020 published data, stores its content internally in WebM and serves GIF only when the client explicitly requests it — serving WebM when the browser supports it (all modern browsers since 2013). Tenor, acquired by Google in March 2018 for $40 million, also converted its storage pipeline to WebM after the acquisition.
Convertir.ai runs GIF to WebM conversion entirely in the browser using FFmpeg.wasm. The technical process starts with GIF format analysis: FFmpeg's GIF decoder reads the header block (GIF87a or GIF89a), the global color table (up to 256 colors in RGB palette), and individual image blocks with their optional local color tables and graphic control extensions (which specify the delay between frames in hundredths of a second and the disposal method for the previous frame). Frames are decoded to 8-bit RGB images with expanded palette. If the GIF has a transparent color index declared in the graphic control extension block, FFmpeg converts frames to RGBA (with alpha channel), enabling WebM VP9 generation with transparency using the yuva420p profile. For GIFs without transparency, frames are converted to YUV420p for greater compression efficiency. The VP9 encoder (libvpx-vp9) receives frames with timestamps extracted from GIF delays (converted from hundredths of a second to VP9 timebase units) and generates the VP9 stream with optimized inter-frame prediction. The encoder speed mode (cpu-used) is configured at a quality/speed balance appropriate for interactive browser use. The output WebM includes the Matroska SeekHead element for efficient random access, though for looping web animations sequential access is sufficient. All processing occurs in WebAssembly without sending data to any server, ensuring privacy for personal stickers, corporate memes, or confidential content.