Merge Videos — Real FFmpeg.wasm (Client‑Side)

Drop videos, reorder, choose output format. FFmpeg runs entirely in your browser – no upload, no watermark, free.

Drop videos here or
Output format:
FFmpeg not loaded yet
Initializing FFmpeg.wasm... (first load may take a few seconds)
Note: Merging uses FFmpeg.wasm. Large files may be slow or fail due to browser memory limits. Works best with short clips.

Real Video Merger with FFmpeg.wasm

This tool uses the actual FFmpeg library compiled to WebAssembly, running 100% in your browser. Your videos never leave your device – no privacy concerns, no upload time, no watermarks.

How it works:

  • FFmpeg.wasm is loaded once (cached afterwards).
  • Your videos are read directly into memory and processed locally.
  • The merged video is downloaded as a new file with an auto‑generated name.

Because it’s real FFmpeg, you get the same quality as command‑line tools. The “fast concat” option attempts to copy streams without re‑encoding (much faster, but requires identical codec/resolution). Uncheck it to force a full re‑encode (compatible but slower).


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