Merge MP3, WAV, M4A and other audio files into one track, with an optional gap or crossfade between them. Everything happens in your browser and nothing is uploaded.
Audio Joiner
Merge MP3, WAV, M4A and other audio files into one track, with an optional gap or crossfade between them. Everything happens in your browser and nothing is uploaded.
The Audio Joiner reads your clips and merges them on your device. Nothing is uploaded to ArrayKit, and the joined file exists only in your browser until you download it.
The Audio Joiner stitches several audio files into a single track, in the order you set. Drop your clips, drag them into place or nudge them with the arrow buttons, and each one shows its length and the exact moment it will start in the finished file. Between clips you can leave a straight cut, insert up to ten seconds of silence, or crossfade up to five seconds so one track melts into the next. Because files from different sources rarely share a sample rate or channel layout, every clip is first converted to the settings you choose, which stops a 48 kHz recording from playing at the wrong speed next to a 44.1 kHz one. The result downloads as MP3 at your chosen bitrate or as lossless WAV, and the whole job runs on your own device.
Features
Merge any mix of MP3, WAV, M4A, OGG, FLAC and AAC files, including the audio of an MP4
Reorder by dragging a row, with up and down buttons, A to Z or reverse
Shows each clip's length and its start time in the finished file
Optional silent gap of 0 to 10 seconds between clips
Optional crossfade of 0 to 5 seconds, automatically shortened next to very short clips
Normalises sample rate and mono or stereo so mismatched files join cleanly
Export MP3 at 96 to 320 kbps or lossless WAV, with a size estimate before you start
Runs locally, so your recordings are never uploaded
How to use the Audio Joiner
Drop two or more audio files onto the page, or click to choose them
Drag the rows or use the arrows until the clips are in the order you want
Pick a straight cut, a silent gap or a crossfade, and set its length
Choose MP3 or WAV, then the bitrate and sample rate
Press Join, listen to the preview and download the merged file
intro-joined.mp3 — 25:01, about 34 MB
episode starts at 0:18, outro starts at 24:26
Each crossfade overlaps two seconds, so the total is four seconds shorter than the clips added together.
Common errors & troubleshooting
The joined file is shorter than the clips added together. — That is the crossfade. An overlap of two seconds removes two seconds at every boundary. Switch to a gap or a straight cut if you want every second preserved.
One clip has a dash instead of a length. — The browser could not read that file's duration, often because of an unusual codec. It can usually still be joined, but the total shown is then a minimum and a crossfade next to it may be shorter than requested.
A clip was skipped when I dropped the files. — Only files that look like audio are accepted. Images, documents and archives are ignored, and a notice above the list says how many were left out.
Joining a large set stops with a memory error. — All the clips and the result are held in memory while they are processed. Join in two batches, lower the bitrate, or choose MP3 instead of WAV to keep the result small.
Frequently asked questions
Can the Audio Joiner merge MP3 and WAV files together?
Yes. Each clip is converted to the sample rate and channel layout you pick before the clips are joined, so an MP3, a WAV and an M4A can sit in the same list and come out as one consistent file in the format you choose.
What is the difference between a gap and a crossfade when joining audio?
A gap inserts real silence between two clips, up to ten seconds, so the total grows. A crossfade overlaps the end of one clip with the start of the next while the first fades out and the second fades in, up to five seconds, so the total shrinks by the overlap.
Will merging lose audio quality?
Choosing WAV keeps the result lossless, apart from the sample-rate conversion. Choosing MP3 encodes the joined audio once at the bitrate you select, so 192 kbps or higher is a sensible choice for music, and lower rates suit speech.
How many files can I combine in one go?
There is no fixed count. The practical limit is your device's memory, because every clip and the finished file are held in memory during the join. A few dozen songs or a long list of short voice notes is usually fine on a laptop.
In what order does the Audio Joiner put the clips?
Top to bottom, exactly as listed. Files you add later go to the end, and you can drag any row, use the arrows, sort A to Z with natural numbering so track 2 comes before track 10, or reverse the whole list.
Are my recordings uploaded when I merge audio here?
No. The clips are read and joined on your device and the result is created in the browser, so voice notes, interviews and unreleased music never leave your computer or phone.
Related tools
Audio Trimmer — Cut a clip from an audio file with optional fades, losslessly where possible.
Audio Converter — Convert audio between MP3, WAV, FLAC, M4A and OGG with bitrate control.
Audio Volume Changer — Raise, lower or normalise the volume of a video or audio file in your browser.
Extract Audio from Video — Extract the audio from a video as MP3, WAV or M4A, in your browser — nothing uploaded.
Voice Recorder — Record from your microphone, trim the take and save it as WAV or the original format.
Video Merger — Join clips into one video — lossless when they match, auto-scaled to MP4 when not.
Add Music / Replace Audio — Replace the audio in a video with your own music and adjust the volume, in your browser.