01 — The tool
Merge audio files into one continuous recording
The free Loudness.ai Audio Joiner puts separate recordings in sequence and exports one WAV file. Combine podcast sections, join voice notes or arrange music passages. Each clip keeps its place in the sequence, with its own volume control and an option to move or remove it.
Choose a direct join when one clip should finish before the next begins. Use crossfade to overlap their edges and blend a music transition. Preview the complete sequence before saving. If your tracks need to play at the same time, use the Audio Mixer to layer them instead.
02 — How it works
How to join MP3 and WAV files online for free
Add the recordings
Choose the audio files for your sequence. The MP3 joiner accepts up to 12 recordings, with each file up to 500 MB. Check their names and order before editing.
Arrange clips and transitions
Drag recordings into order or use the move buttons. Adjust louder clips with their volume sliders. Choose Direct join or Crossfade, then set the overlap duration when crossfade is enabled.
Listen and download
Play the sequence and check each transition. Add an opening or closing fade if needed, choose 16-bit or 24-bit WAV, enter a filename and click Export audio.
03 — Practical uses
Combine podcast sections, voice notes and songs
Podcast introductions and interviews
Place the introduction, conversation and closing in order. Use direct joins between spoken sections so words remain separate. Trim long pauses in individual clips with the Audio Cutter before joining.
Join voice notes
Combine audio messages or narration takes into one recording. Compare each voice's level and lower a louder clip, so listeners do not need to change their playback volume at every boundary.
Join songs with crossfade
Blend neighboring music clips with a short overlap. Listen for competing vocals or mismatched beats. Shorten the overlap or switch to a direct join when a clean musical boundary sounds better.
04 — Frequently asked questions
Audio Joiner questions
Does joining audio overlap all the tracks?
Direct join plays clips one after another. Crossfade overlaps only neighboring edges. The joiner does not stack full recordings on top of each other; that workflow belongs in an audio mixer.
Why is the joined file shorter with crossfade?
Overlapping time is counted once. Two 30-second recordings with a 1-second crossfade produce a 59-second sequence. Longer overlaps reduce the total duration further, within each clip's available length.
Can I combine different audio formats?
Yes. Add supported MP3, WAV, M4A or other recordings to the same sequence. The exported result is one WAV file. Use the Audio Converter afterwards if you want MP3 output.
Is the online audio joiner free?
Yes. Arrange and join recordings without signing up. Preview the sequence before exporting, and keep your source recordings for future edits. The merged WAV is saved as a separate download.