About the Audio Merger
Audio Merger stitches multiple audio files into a single lossless WAV — sequencing tracks back-to-back, trimming each one, applying per-track fade in/out, and optionally crossfading between consecutive clips. Drop two or more files, arrange the order, fine-tune the timing, preview the result on a live waveform, then render the final mix.
Everything happens inside your browser using the Web Audio API and OfflineAudioContext. Your files are never uploaded, never queued on a server, and never logged. Close the tab and they're gone — safe for unreleased music, voice memos, client work, or anything else you'd rather not hand to a third party.
What you can control
- Multi-format input: MP3, WAV, OGG, M4A, and anything else the browser can decode — mix formats freely in one project.
- Project sample rate: Default 44,100 Hz for maximum compatibility. Bump up to 48,000 / 96,000 Hz for higher-fidelity work.
- Per-track trim: Set precise start and end times in seconds to slice each source down to the segment you want before mixing.
- Per-track fade in / fade out: Smooth the head and tail of each clip individually.
- Default crossfade: Set a single number and consecutive tracks automatically overlap by that duration — great for seamless playlists or DJ-style mixes.
- Headroom gain (dB): Pull peaks down (default −1.0 dB) to prevent clipping when overlapping tracks stack up.
- Reorder tracks: Use the arrow keys or buttons to shuffle the running order without re-uploading.
- Waveform preview: Scrubbable visual playhead — click anywhere on the waveform to jump to that position before you commit to a render.
- Lossless WAV export: The final render is a high-quality, uncompressed WAV file.
Common uses
- Combining voice memos or interview takes into a single edited file.
- Building seamless podcast episodes from intro, segments, ads, and outro clips.
- Stitching together music demos and stems for sharing or further mixing.
- Creating crossfaded playlists or workout mixes from individual songs.
- Joining audiobook chapters, language-lesson recordings, or meditation tracks.
- Merging multi-take voiceovers for video projects before laying them over picture.
Tips for the best results
- Set every track's fade in/out to 0.05–0.1s as a safety net to avoid pops at the join points, even without a full crossfade.
- For musical mixes, try a global crossfade of 2–4 seconds. For spoken word, 0.1–0.3s usually feels right.
- Keep headroom around −1.0 to −3.0 dB if you're crossfading loud material — overlapping peaks can clip otherwise.
- Stick to 44,100 Hz unless you have a specific reason. Most distribution platforms expect 44.1 or 48 kHz.
- Preview the full mix before rendering — the waveform reflects every fade, trim, and crossfade exactly as it'll export.
- Trim leading silence from each source with the Start input. It's faster than re-encoding the files elsewhere.
No accounts, no upload queue, no length limits — drop your audio, arrange the order, and render. The final WAV is yours to compress, distribute, or mix further in any DAW.
Common questions
How do I combine multiple MP3 files into one?
Add your files in order, trim each segment if needed, and export a single merged file. A preview lets you hear the full sequence before downloading.
Can I add crossfades so the joins are seamless?
Yes. Add fade-ins, fade-outs, and crossfades between segments so one track melts into the next instead of cutting hard. It is the difference between a playlist and a mix.
Can I merge a podcast intro, episode, and outro?
That is the classic use. Trim each piece, crossfade the joins, preview the whole episode, and export one clean file ready to upload to your host.
What format does the merged file come out in?
The merger exports WAV for full quality. If you need MP3 or another format afterward, run the result through our audio converter in one more step.
Do my recordings get uploaded anywhere?
No. Merging happens entirely in your browser, so interviews and voice memos never leave your device.
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