Simply upload your video and the new audio file, then click "Start Processing." The tool uses ffmpeg.wasm to run entirely in your browser — your video's original audio track is removed and replaced with the new one, while keeping the video quality intact. No files are ever uploaded to any server.

Absolutely. All processing happens locally in your browser using WebAssembly (ffmpeg.wasm). Your video and audio files never leave your device. This means complete privacy — no uploads, no server storage, no third-party access. You can even disconnect your internet after the page loads and the tool will still work.

Video input: MP4, WebM, MOV, AVI, MKV, FLV, and most common formats.
Audio input: MP3, WAV, AAC, OGG, FLAC, M4A.
Output: MP4 for video (with replaced/removed audio), MP3 for extracted audio. The tool automatically handles format conversion during processing.

Processing time depends on your video's size and length, as well as your device's performance. Small videos (under 50 MB) typically process in 10–30 seconds. Larger files may take a few minutes. The "Remove Audio" operation is fastest since it simply copies the video stream. For best results, we recommend videos under 200 MB for a smooth experience, especially on mobile devices.

Remove Audio creates a muted video file — the video stays intact but all sound is stripped away (output: MP4 with no audio track).
Extract Audio pulls just the audio track from your video and saves it as a separate MP3 file — perfect for creating podcasts, ringtones, or music samples from video content. The original video file is not modified or saved in this mode.

On first visit, the tool downloads a small processing engine (~25 MB) called ffmpeg.wasm. This is what enables professional-grade video/audio processing directly in your browser. The download only happens once — subsequent visits will use the cached version, making the tool load almost instantly. A loading indicator will keep you informed during this one-time setup.

Yes! The tool is fully responsive and works on mobile browsers. However, mobile devices have less processing power and memory, so we recommend keeping video files under 100 MB for the best mobile experience. For very large files, a desktop browser will provide faster processing. The interface adapts seamlessly to any screen size.

No — when replacing or removing audio, the video stream is copied directly without re-encoding. This means zero quality loss for the visual portion of your video. Only the audio track is processed. The output video will look exactly like the original, just with different sound (or no sound, depending on your chosen operation).