Audio Tools
Audio Merger
Merge multiple audio files into one with reordering, gap control, and crossfade options.
Drop audio files or click to upload
MP3, WAV, OGG, FLAC, AAC, M4A, WebM — up to 20 files
🔒 Your audio files are processed in your browser. OptiPix never hears your recordings.
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About Audio Merger
OptiPix Audio Merger combines 2-20 audio files into a single track directly in your browser. Upload multiple audio files, reorder them with drag-and-drop controls, and set gap durations between tracks. Export in MP3, WAV, OGG, FLAC, or AAC with adjustable bitrate. The merger handles different input formats automatically — mix MP3, WAV, and OGG files in the same merge. Uses FFmpeg.wasm concat demuxer for high-quality output. All processing happens locally.
How It Works
The tool writes all input files to FFmpeg.wasm's virtual filesystem, creates a concat list, then runs the FFmpeg concat demuxer to join them in order with optional gaps between tracks.
Use Cases
- •Combine podcast segments into one episode
- •Merge audiobook chapters
- •Join music tracks for a mixtape
- •Combine voice recordings
- •Create a presentation soundtrack
Frequently Asked Questions
How many files can I merge?
Can I reorder the tracks?
Can I add silence between tracks?
Do all files need to be the same format?
Is my audio uploaded?
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