{"$schema":"https://toolsly.tools/schemas/tool-manifest-v1.json","generated":"2026-06-02T15:45:19.753Z","discovery":{"catalog":"https://toptool.io/tools.json","llmsTxt":"https://toptool.io/llms.txt","sitemap":"https://toptool.io/sitemap.xml"},"relatedTools":[{"slug":"mp4-to-webm","name":"MP4 to WebM","url":"https://toptool.io/mp4-to-webm"},{"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":"mkv-to-mp4","name":"MKV to MP4","url":"https://toptool.io/mkv-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":"webm-to-mp3","name":"WEBM to MP3","url":"https://toptool.io/webm-to-mp3"},{"slug":"mp4-to-aac","name":"MP4 to AAC","url":"https://toptool.io/mp4-to-aac"}],"kind":"converter","slug":"webm-to-mp4","name":"WebM to MP4","description":"Convert WebM video to MP4 (H.264 + AAC) — free online, no upload.","longDescription":"Re-encode a WebM file as an MP4 with H.264 video and AAC audio — the most universally playable video format, supported by every phone, TV, and editor. The conversion runs locally via ffmpeg.wasm, so your file never leaves your browser. 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":["webm to mp4","convert webm to mp4","webm to mp4 converter","webm to mp4 online","webm to mp4 free","online webm to mp4","change webm to mp4","webm mp4 converter","free webm to mp4","online webm to mp4 converter","webm to h264","encode webm as mp4"],"url":"https://toptool.io/webm-to-mp4","runsOn":"client","multiple":false,"batch":false,"input":{"type":"file","extensions":[".webm"],"mimeTypes":["video/webm"]},"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/webm-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."}}