Does changing the speed change the pitch?

No. The tempo is changed with a pitch-preserving filter, so voices keep their natural tone - no chipmunk effect when speeding up and no deep growl when slowing down. This also means it is not a pitch shifter: if you want the key of a track changed, this tool will not do that.

Which speeds can I pick?

0.5×, 0.75×, 1.25×, 1.5×, 1.75×, 2×, or 3×. One speed applies to every file in the batch, so run separate jobs if you need different speeds for different files.

What format do the files come back in?

The same format they went in: MP3 stays MP3, M4A stays M4A, WAV stays WAV, FLAC stays FLAC, and OGG stays OGG. AAC comes back as M4A, and OPUS and WMA come back as MP3 so the output plays everywhere.

No. No AI model touches your audio - the speed change is fully deterministic. The same input and speed always produce the same output.

How is pricing calculated?

2 credits per file, with a 2-credit minimum. Retiming ten files in one batch is 20 credits, regardless of the speed you pick.

Yes. Processing runs on our own servers, your files are never sent to a third party or used to train a model, and everything is auto-deleted 7 days after the job finishes.

← All tools

Audio → retimed audio2 credits / file

Change Audio Speed

Lectures, audiobooks, meetings, and dictation → the same recording at 0.5× to 3× speed, with the voices kept at their natural pitch.

50 credits free every month

No card needed

Private files

Add your files

Upload after your free sign-upMP3, M4A, WAV, AAC, FLAC, OGG, OPUS, or WMA · up to 500 MB each

Speedexpand_moreAvailable after sign-up

Choose your settings after sign-up.

Secure upload

EXAMPLE

UPLOADED - ORIGINAL SPEED

arrow_forward

RETIMED - 1.5× FASTER

lecture.mp3 → lecture-1.5x.mp3 40 min

audiobook-ch3.m4a → audiobook-ch3-1.5x.m4a 18 min

standup.wav → standup-1.5x.wav 10 min

interview.ogg → interview-1.5x.ogg 22 min

What you get

check_circleEvery file retimed to the speed you picked, from 0.5× to 3×

check_circlePitch preserved - no chipmunk voices, no slowed-down growl

check_circleOriginal format kept - an MP3 comes back as an MP3

check_circleOutputs named after the source with the speed appended

check_circleA single file downloads on its own; a batch comes back as one zip

How it works

1Upload your audioDrop in any mix of MP3, M4A, WAV, AAC, FLAC, OGG, OPUS, and WMA files - one clip or a whole batch - and pick a speed from 0.5× to 3×.

2Every file is retimedEach upload is re-encoded at the new tempo with a pitch-preserving filter, so voices keep their natural tone. No AI model touches your audio - the change is fully deterministic.

3Download the retimed filesOne output per upload, in the original format and named with the speed - lecture.mp3 → lecture-1.5x.mp3. A single file downloads on its own; a batch comes back as one zip.

Who uses this tool

EDUCATION

Lectures in half the time

Speed recorded lectures up to 1.5× or 2× and get through a course backlog without losing the natural sound of the speaker.

AUDIOBOOKS & PODCASTS

Listen faster than the app allows

Retime episodes and chapters to a fixed 2× or 3× so they play at your pace on any player, even ones without a speed control.

TRANSCRIPTION & TYPING

Dictation slow enough to type

Slow a dictated memo or interview to 0.75× or 0.5× so your typing keeps up without constant pause-and-rewind.

TEAMS & MEETINGS

Catch up on recorded calls

Run the meetings you missed at 1.5× and still hear every word clearly - the pitch stays natural, only the tempo changes.

LANGUAGE LEARNING

Native speech at a learnable pace

Slow native-speed recordings to 0.75× so you can follow the pronunciation, without the audio dropping into a distorted growl.

MUSIC & AUDIO

Practice tracks at tempo you choose

Slow a passage down to work through it, or speed a reference up - the key stays the same because pitch is preserved.

SECURITY

Built for sensitive documents

Bank statements, medical files, case records. Security isn't a feature we added - it's the foundation.

lock

Encrypted in transit

Encrypted in transit over TLS 1.2+, and stored in access-controlled, encrypted object storage. Files are protected the moment they leave your browser.

admin_panel_settings

Your files stay yours

Workspaces are isolated per account. Role-based access shows teammates only what they need.

auto_delete

Deleted, not stored

Files are deleted after processing. Everything runs on our own hardware and is never sent to an outside AI service, so your data is never used to train models.

dnsProcessed on our own hardwareauto_deleteDeleted after processinglockEncrypted in transit