MKV to AVIF Converter

Convert MKV to AVIF Online

Pull a single frame out of an MKV video and save it as an AVIF still — the AV1-based image format that lands roughly 50% smaller than a JPEG at the same visual quality. Unlike video-to-AVIF tools that spit out an animated clip, this extracts one sharp frame at the timestamp you choose, so you get a poster image, thumbnail, or screenshot rather than a looping animation. 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 or made public.

How to Convert MKV to AVIF

1. Upload Your MKV File: Drag and drop your video onto the page or click "+ Add Files" to browse. Matroska files can be large, so the practical limit is upload size and time rather than anything on your end.
2. Pick the Frame to Capture: Under Frame Selection, choose Specific Frame and set the Time (seconds) to the exact moment you want — or use Multiple Screenshots to grab several stills across the clip in one pass.
3. Set Quality and Size: Leave the Quality Preset on Very High (Recommended) for a near-lossless still, or switch to Specific file size to cap the output. Use Image resolution to downscale by percentage, a preset, or exact Width × Height.
4. Convert and Download: Click Convert and save your AVIF image. No sign-up, no watermark.

MKV vs AVIF — What You're Actually Converting

Frequently Asked Questions

Does this produce a still AVIF or an animated one?

A still. Many "video to AVIF" converters re-encode a span of frames into an animated AVIF, similar to an animated GIF. This tool extracts a single frame at the timestamp you set under Frame Selection, so the output is one static image. If you want several stills, the Multiple Screenshots option saves a batch from across the clip.

How much smaller is an AVIF frame than the same frame as JPEG?

In our testing, a 1080p frame extracted from an MKV and saved at the Very High preset typically came out 40–55% smaller than the same frame exported as a high-quality JPEG, with fewer blocking artifacts in skies and gradients. The exact ratio depends on scene complexity — flat, smooth frames compress the most.

Why does AVIF conversion take longer than JPEG?

AVIF uses the AV1 codec's intra-frame compression, which is far more computationally expensive than JPEG's. Squeezing that extra efficiency out of a single image takes real encoding work, so an AVIF still can take a few seconds where a JPEG would be near-instant. The payoff is the smaller file at matching quality.

Which browsers and devices can open an AVIF file?

AVIF is supported in roughly 93% of browsers in use today: Chrome 85+, Firefox 93+, Edge 121+, and Safari 16.4+ (macOS 13.3 / iOS 16, from 2023). Older browsers and some image viewers won't open it — if you need maximum compatibility, extract the frame as JPG instead.

Will the extracted frame keep the MKV's resolution and color depth?

By default the still matches the source frame's pixel dimensions, and AVIF can carry 10- or 12-bit color, which preserves smooth gradients better than 8-bit JPEG. You can downscale with the Image resolution controls if you want a smaller thumbnail. Subtitle and audio tracks in the MKV are not part of a single-frame image, so they're dropped.

Can I convert several MKV files to AVIF at once?

Yes. Add multiple Matroska files and they're processed with the same Frame Selection and quality settings. To convert from a different source video instead, the MP4 to AVIF converter does the same frame extraction from MP4 input.