Audio Editor

Online audio editor and MP3 cutter: trim with the waveform or exact times, adjust volume and playback speed, and export to common formats. Optional background music under the main track. Audio or video upload—we use the audio track.

Main track (required)

Background music (optional) — add a bed under the main track

Use loop count and delay below to control how often it plays and when it starts.

Optional BGM file

Remove

BGM volume 1×

BGM play count

0 = loop forever (until the main track ends). 1 = play the BGM file once. 2+ = play it that many times in a row (then silence if the main track is longer).

BGM start delay (ms)

Silence before the BGM is mixed in (default 0).

Processing runs locally in your browser; files are not uploaded.

Combine narration or music with optional background music, set levels, change main-track speed, trim unwanted sections, and download one mixed file.

Tips:

• BGM play count 0 loops the bed for the full length of the main track; a finite count plays the file that many times then stops (remaining main audio is unchanged).
• BGM delay adds silence before the bed starts; it does not shift the main track.
• Speed changes apply only to the main track; BGM keeps its original speed.
• After choosing the main file, drag the blue trim handles on the waveform; if no waveform appears (some videos), use the manual time fields.