How to Change Audio Speed While Keeping Pitch

Choose the change you need

The audio speed tool changes the duration of a recording while keeping its intended pitch. Start at 0.75× for slower practice or 1.25× for faster review. Use 1× to return to the original pace. The supported range is 0.5×–2×.

Calculate the new duration

Divide the original duration by the multiplier. A two-minute recording at 1.5× becomes roughly 80 seconds. At 0.5×, it becomes four minutes. Pauses and silence change length too. The exported result can differ slightly from this estimate because time stretching works with short waveform windows and MP3 has encoding boundaries.

Compare pitch and texture

Listen to the same phrase in both players at the same device volume. Notes should retain their pitch, but repeated beats, consonants and sustained tones may sound less natural at extreme settings. Pitch preservation is not a promise of identical timbre or studio mastering quality. Reduce the change if the result sounds watery, rough or smeared.

Save a file or change playback?

If you only need faster listening once, your player may already have a speed control. Exporting creates a permanent copy for other apps, but MP3 is encoded again. At 1×, AudioEditorKit bypasses time stretching while still performing the selected export conversion.

Prepare a practice section

Use audio trimming to isolate a phrase before slowing it down. A shorter file is easier to compare and needs less browser memory. Keep original recordings separately. For multiple sections, use audio merging after editing, checking every transition.

Pick the format and check storage

WAV export stores uncompressed 16-bit PCM. MP3 provides smaller files at a chosen bitrate but is lossy. A slowdown increases duration and usually file size at unchanged settings. The file size calculator and bitrate guide explain the tradeoffs. Exporting WAV cannot recreate detail missing from an MP3 source.

Check the final copy

1. Choose a mono or stereo MP3 or PCM WAV, one second to ten minutes and at most 30 MiB.
2. Set a speed, then review expected duration.
3. Create the result and compare both players, including the opening and ending.
4. Check actual duration and file size, then download the copy.

Changing speed clears the previous result so you cannot accidentally download an old setting. A new file resets the multiplier to 1×. For decoding or saving problems, see processing help. Browse all audio guides for related tasks.