Any file up to 500 MB. Drop several files and they come back as one ZIP. Many image, audio and video conversions run in your browser; anything else is uploaded and removed within the hour.
Convert your high-definition MKV files to the widely compatible AVI container format. This tool is ideal for users who need to play modern video files on older hardware or legacy software.
Both MKV and AVI are multimedia containers designed to hold video, audio, and subtitle streams. While MKV supports advanced features like soft subtitles and multiple audio tracks, AVI is a much older standard based on the Resource Interchange File Format (RIFF). Converting from MKV to AVI involves repackaging these streams into a structure that older media players can parse, effectively stripping away features unsupported by the AVI specification while maintaining compatibility.
Since both formats use lossy compression, the conversion process requires re-encoding the video streams, which inevitably leads to a slight loss in visual fidelity.
We built this project so anyone can convert files without paywalls, accounts, or hidden limits. Here is what that promise means in practice.
Every converter on ConvertX is free to use: no trials, no premium tiers, and no credit packs. We will never put core conversion features behind a subscription. Whether you convert one photo or a hundred files a week, the price stays zero.
Many image, audio, and video conversions run entirely in your browser. Your files never leave your device for those jobs. When server processing is required for documents or specialized formats, uploads are handled securely and removed automatically — typically within one hour.
A quick guide to strengths and trade-offs of popular formats — so you pick the right one before converting.
Clips, streams, screen recordings, and movies.
Common extensions: MP4, WebM, MOV, MKV, AVI, MPEG
Raster and vector graphics for web, print, and photography.
Common extensions: PNG, JPG, WebP, AVIF, GIF, SVG, HEIC, TIFF
Office files, PDFs, ebooks, and plain text.
Common extensions: PDF, DOCX, XLSX, PPTX, ODT, EPUB, TXT
Music, podcasts, voice recordings, and sound effects.
Common extensions: MP3, WAV, FLAC, OGG, AAC, M4A, OPUS
