{"$schema":"https://toolsly.tools/schemas/tool-manifest-v1.json","generated":"2026-06-02T15:45:19.759Z","discovery":{"catalog":"https://toptool.io/tools.json","llmsTxt":"https://toptool.io/llms.txt","sitemap":"https://toptool.io/sitemap.xml"},"relatedTools":[{"slug":"mp4-to-mkv","name":"MP4 to MKV","url":"https://toptool.io/mp4-to-mkv"},{"slug":"video-trimmer","name":"Video Trimmer","url":"https://toptool.io/video-trimmer"},{"slug":"video-compress","name":"Compress Video","url":"https://toptool.io/video-compress"},{"slug":"webm-to-mp4","name":"WebM to MP4","url":"https://toptool.io/webm-to-mp4"},{"slug":"avi-to-mp4","name":"AVI to MP4","url":"https://toptool.io/avi-to-mp4"},{"slug":"mov-to-mp4","name":"MOV to MP4","url":"https://toptool.io/mov-to-mp4"},{"slug":"mp4-to-webm","name":"MP4 to WebM","url":"https://toptool.io/mp4-to-webm"},{"slug":"mp4-to-aac","name":"MP4 to AAC","url":"https://toptool.io/mp4-to-aac"}],"kind":"converter","slug":"mkv-to-mp4","name":"MKV to MP4","description":"Convert MKV (Matroska) video to MP4 (H.264 + AAC) — free, runs in your browser.","longDescription":"Re-encode an MKV file to MP4 with H.264 video and AAC audio so it plays on every phone, TV, and editor. We re-encode rather than remux because MKV files often contain codecs (HEVC, FLAC, subtitles) that MP4 doesn't carry the same way — re-encoding guarantees a clean, broadly compatible result. The conversion runs locally via ffmpeg.wasm, so your file never leaves your device. Performance depends on your CPU: expect roughly real-time encoding for short clips (a 5-minute 720p video may take 1–2 minutes). Sources taller than 1080p are automatically downscaled to 1080p so the browser does not run out of memory mid-encode; for best results keep inputs under about 500 MB.","category":"video","categoryName":"Video","keywords":["mkv to mp4","convert mkv to mp4","mkv to mp4 converter","mkv to mp4 online","mkv to mp4 free","online mkv to mp4","change mkv to mp4","mkv mp4 converter","free mkv to mp4","online mkv to mp4 converter","matroska to mp4","mkv to h264"],"url":"https://toptool.io/mkv-to-mp4","runsOn":"client","multiple":false,"batch":false,"input":{"type":"file","extensions":[".mkv"],"mimeTypes":["video/x-matroska","video/mkv"]},"output":{"type":"file","extension":".mp4","mimeType":"video/mp4"},"options":[{"type":"number","key":"crf","label":"Quality (CRF)","defaultValue":23,"min":18,"max":30,"step":1,"help":"Constant Rate Factor — lower = better quality and larger file. 23 is a sensible default; 18 is visually lossless; 28+ is heavy compression."}],"invocation":{"webUi":"https://toptool.io/mkv-to-mp4","api":null,"notes":"Currently runs client-side in the user's browser. Drop a file on the UI at `webUi` and download the converted result. A remote MCP/REST API is planned."}}