How to Merge Audio Files in the Right Order

Plan the sequence before exporting

Start with a clear list of the parts you want to hear: an introduction, the main recording and an ending, for example. The audio merger places them one after another. It does not play them simultaneously. If you want music underneath a voice recording, use a multitrack editor instead.

Use descriptive filenames, but check the numbered list rather than assuming the browser sorted files by name. You can select several files together, add another batch, remove an item, or move each item up and down. A repeated file will play twice if it appears twice; duplicate names are not automatically removed.

Prepare the beginnings and endings

Preview every source before joining. A recording may contain several seconds of silence, a spoken countdown or an unfinished sentence. Use audio trimming to remove unwanted material, then select the edited copy for your sequence. Keep a separate original so you can revise the cut later.

Joining does not overlap files or add a crossfade. Existing silence remains, and a hard cut between unrelated waveforms can click. If an edge needs softening, apply a short fade-in or fade-out beforehand. Listen to whether that pause suits the sequence; fading both sides is not the same as a continuous crossfade.

Understand the shared output format

MP3 and uncompressed PCM WAV sources can share one merge. AudioEditorKit converts them to 44.1 kHz stereo before joining. Other sample rates are resampled. Mono audio is copied to the left and right channels equally, while stereo audio retains separate channels. This makes the output consistent but means the result does not preserve every original technical setting.

If you ultimately need one mono channel, you can use stereo to mono on a WAV export. Read the mono mixing guide first: opposite-polarity stereo sounds may cancel during that later mix. The merger itself keeps stereo channels separate.

Compare levels at the transitions

A quiet phone recording followed by a louder music file can be uncomfortable even when both sound fine separately. Play them at the same device volume and compare the join. This tool does not measure integrated loudness or automatically normalize recordings. Use volume adjustment for a manual correction and watch for clipping when increasing gain.

Lowering an overly loud section is often easier to evaluate than raising a quiet section without knowing its peak level. Listen again after any adjustment. Changing your speaker volume changes only playback, not the loudness stored in the exported file.

Choose MP3 or WAV deliberately

MP3 is useful for sharing a smaller final file. The selected bitrate applies to the complete stereo stream, and the assembled audio is encoded once. It is still a lossy export, even if all source files were already MP3. Increasing the bitrate does not restore details lost earlier.

WAV stores the joined audio as 16-bit PCM. At 44.1 kHz stereo, one minute uses about 10.1 MiB before headers, so it can be much larger than an MP3. It is useful when you plan further editing, though resampling and conversion to 16-bit may still change original samples. The file size calculator helps estimate storage before exporting.

Check and save the finished recording

1. Choose 2–8 supported files within the combined 30 MiB and ten-minute limits.
2. Confirm the order and preview each source.
3. Choose the output format and merge.
4. Compare the displayed duration with the sum of your parts. Seek to every join in the result player.
5. Download the final file and keep the sources separately. Changing the order or settings clears the old result and requires another merge.

If a selection contains an unsupported file, none of that new batch is added and the earlier list remains available. Remove the problem file from your selection and try again. Smaller batches can help if the browser runs out of memory. For other errors, see audio processing help, or return to all guides.