AudioBento

Audio Speed Changer

Speed up or slow down audio from 0.25× to 4.00×. Preview with Preserve pitch on or off, then export MP3 or WAV locally in your browser.

Related Audio Tools

Audio JoinerJoin audio files in your preferred order.Audio TrimmerKeep or remove a section of audio.Ringtone MakerCut songs or recordings into custom ringtones.Fade AudioAdd fade in and fade out to audio.Reverse AudioTurn your recording into backwards audio.Audio Speed ChangerSpeed up or slow down your audio.

How to change audio speed

  1. 1

    Choose your audio

    Select one MP3, WAV, M4A, FLAC, OGG, or AAC file. Listen to Original at normal speed before making changes.

  2. 2

    Set the speed and listen

    Set Speed from 0.25× to 4.00×. Compare Original and Preview, and turn Preserve pitch on or off to hear the difference.

  3. 3

    Change speed and download

    Choose MP3 with a bitrate, or WAV. Click Change speed, listen to the exported audio in Result, then download.

Find a tempo that fits your task

Listen at a new speed, compare with Original, and check the exported recording.

01

Control tempo with a single slider

Choose a slower or faster pace. Preserve pitch keeps the original key; switch it off for the natural higher or lower pitch of faster or slower playback. Preview and export can still sound different.

  • 0.25× takes about four times the original time.
  • At 1.00×, Change speed shows a no-change message.
  • 4.00× takes about one quarter of the original time.

Example speed and expected duration

Speed
2.00×
Duration relative to Original
0.50×

Original → Preview

02

Follow speech at your own pace

Slow down a spoken recording to review unfamiliar words, or speed it up when the pace feels too slow. Compare small changes before exporting. Clarity depends on the source and on how far you move from normal speed.

  • Use a slower tempo for language listening.
  • Try a faster pace for a lecture or interview.
  • Switch to Original to compare normal timing.

Example speed and expected duration

Speed
0.75×
Duration relative to Original
1.33×

Original → Preview

03

Practice with slower music

Reduce tempo to follow a phrase or practice timing. Keep Preserve pitch enabled when you want the notes to stay at their original pitch. Larger speed changes can introduce audible artifacts. Listen to the export before using it for practice.

  • Slow down the whole recording for practice.
  • Pitch preservation does not guarantee identical sound.
  • This tool does not isolate instruments or change key.

Example speed and expected duration

Speed
0.50×
Duration relative to Original
2.00×

Original → Preview

04

Fit a recording to a new duration

Increase speed to shorten the entire recording, or reduce speed to make it longer. At 1.50×, duration is about two thirds of the source. Choose MP3 or WAV and check the actual processed file before using it in a project.

  • Expected duration is source duration divided by speed.
  • Slower exports need more output storage.
  • Your previous result stays available until a new one is ready.

Example speed and expected duration

Speed
1.50×
Duration relative to Original
0.67×

Original → Preview

Audio speed changer questions

What do 0.25×, 1×, and 4× mean?
0.25× takes four times as long, 1× keeps the normal pace, and 4× takes one quarter of the original time. At 1×, clicking Change speed shows a no-change message. Set the speed from 0.25× to 4.00× in steps of 0.05×.
How is a speed changer different from a pitch changer?
A speed changer changes tempo and duration. With Preserve pitch enabled, it aims to keep the original key. Turn it off to change pitch together with speed. A pitch changer adjusts pitch independently; this tool has no separate semitone or key control.
Does Preview sound exactly like the export?
With Preserve pitch on, Preview uses browser pitch preservation and export uses FFmpeg tempo processing. With it off, both speed up or slow down the audio and its pitch. The algorithms can sound different; after export, use the Result player to hear the processed file before downloading.
Will changing speed keep the original sound quality?
Tempo processing can introduce audible artifacts, especially near the ends of the speed range. MP3 export also uses lossy encoding. WAV avoids another MP3 encoding step, but does not restore lost detail or guarantee an unchanged pitch or sound.
Is my audio uploaded or saved online?
Your audio stays on your device during preview and processing. On export, the browser downloads the FFmpeg program from a CDN without sending your audio there. This local tool needs no account and does not keep online history or process audio on a server.
Which input and output formats can I use?
Choose MP3, WAV, M4A, FLAC, OGG, or AAC that your browser can play, within 2 channels and 48 kHz. Export as MP3 with a selected bitrate or as WAV. The bitrate setting appears only for MP3. Unsupported or damaged files show an error.
Why can a slow export exceed the file budget?
At 0.25×, output lasts about four times as long and can be much larger. Input budgets are 200 MB on desktop and 100 MB on mobile. The tool checks output size using the changed duration before processing. Try MP3 or a shorter source if WAV is too large.
What happens when I change settings after export?
Changing speed, Preserve pitch, format, or MP3 bitrate updates the next export only. Your previous download remains available until a new export succeeds. Preview uses your current speed setting. At 1.00×, Change speed shows a message and skips processing.

Listen at a new pace

Choose your audio, set a speed, and preview the changed tempo.