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YOUR NEXT GREAT SOUND STARTS HERE

Audio Joiner

Different tracks.
One seamless sound.

Bring music, voice notes and recordings together. Trim, arrange and blend your tracks into one seamless mix — right in your browser.

  1. Choose a file
  2. Adjust settings
  3. Review & save
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Files stay on your deviceAlways free · No registration
YOUR MIXING DESK

Bring your sounds together.

A great mix starts with a few tracks.

Drop your audio files here, or add them from your device.

MP3, WAV, M4A, FLAC, OGG & more supported codecs
Up to 20 tracks · 350 MB combined · 10 minutes total source audio
Add two or more tracks to start
LESS FUSS. MORE FLOW.

Everything you need for a seamless mix.

A few thoughtful controls. A sound that comes together.

Your tracks. Your order.

Add multiple files, then move any track up or down. Each clip keeps its own selection and fade settings when you rearrange it.

Keep just the right moments

Drag the cyan handles with a mouse or touch. Use arrow keys on a focused handle, or type exact start and end times in seconds.

Make every transition flow

Join without a gap, or choose a crossfade at each boundary. Set separate fade-in and fade-out lengths for individual clips.

Listen before you download

Preview a selected track or the complete mix with the real trims, fades and crossfades. Export uses the original sources.

Different files. One sound.

Open common MP3, WAV, M4A/AAC, FLAC, OGG and Opus files. Save one MP3, WAV, FLAC or OGG at 44.1 kHz stereo.

Keep your audio close

Audio processing happens in your browser. Files are not uploaded. Up to 20 tracks, 350 MB combined and 10 minutes of total source audio.

FROM FIRST TRACK TO FINAL MIX

How to join audio online

  1. 01

    Add your audio files

    Choose at least two supported files. The local audio engine downloads on first use. Your media is never uploaded.

  2. 02

    Shape the flow

    Select a track, trim its interval, rearrange the order and choose fades or crossfades. Preview a track or the full mix.

  3. 03

    Join, listen and download

    Choose MP3, WAV, FLAC or OGG. Join the audio, download your result and listen once more before sharing.

YOUR NEXT SMALL WIN

A few tracks. One mix worth keeping.

Bring your sounds together with precise intervals and smooth transitions.

Free · No registration · No time limit
  1. 01

    Add two or more audio tracks

    Choose supported files from your device. Review the waveforms; files stay in your browser.

  2. 02

    Trim, arrange and blend

    Set an interval for each track, reorder clips and add fades or crossfades. Preview the selected track or complete mix.

  3. 03

    Join and download

    Choose MP3, WAV, FLAC or OGG, use Join audio and download your finished mix. Listen once more before sharing.

Before you start350 MB combined input · 20 tracks · 10 minutes total source audio · 120 MB output · Codec and device memory limits apply. Free, without registration or time limits; file and device limits still apply.

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A LITTLE CLARITY

Audio Joiner: questions & answers

Useful answers. Clear next steps.

At a glance

Audio Joiner combines selected intervals from multiple supported audio files into one download. Add at least two tracks, reorder them, trim each interval, set fades or crossfades and preview the mix. Processing stays in your browser. Limits: 20 tracks, 350 MB combined source files, 10 minutes total source audio and 120 MB output. Exports are 44.1 kHz stereo MP3, WAV, FLAC or OGG.

How do I merge MP3, M4A or WAV files?

Add at least two supported files, arrange their order, set the intervals you want to keep, choose a format and use Join audio. Download the single resulting file. Input codecs must be supported by the local audio engine.

Can I trim and reorder each audio track?

Yes. Select a track and drag its cyan handles, use arrow keys on a focused handle or enter start/end seconds. Use the up/down buttons to reorder tracks and the delete button to remove one. Edits stay attached to their track.

How does crossfade work?

Crossfade overlaps the end of one selected clip with the beginning of the next. Set Crossfade to next on each boundary. Zero gives a gapless join. Each crossfade can be up to 10 seconds, and adjacent overlaps together must leave at least 0.01 seconds of the clip outside the overlaps. The joined duration is reduced by the overlaps.

Which audio formats and limits are supported?

Common MP3, WAV, AAC/M4A, FLAC, OGG and Opus codecs are supported; damaged or unsupported files show an error. Use up to 20 tracks within 350 MB combined and 10 minutes total source audio. Output is limited to 120 MB and uses MP3, WAV, FLAC or OGG at 44.1 kHz stereo. Device memory can impose lower practical limits.

Does joining change audio quality?

Trimming, fades and crossfades process the original sources. Output is normalized to a common 44.1 kHz stereo format. MP3 and OGG are re-encoded using lossy codecs; WAV and FLAC preserve the processed audio without an additional lossy encoding step. Preview and check the result before sharing.

Are my audio files uploaded?

No. The audio engine downloads on first use and processes your files inside your browser. Audio files and previews are not uploaded or placed in the site service-worker cache. Closing the workspace releases its files and results.

Is Audio Joiner free to use?

This tool is completely free without registration, payment or a session time limit. Use it as often as you like. Published file, codec and device-memory limits still apply. Other tools have separate access rules.

Still need a little help?Contact our team