Tools › Audio Tools › Audio Speed Changer

Audio Speed Changer — Speed Up or Slow Down MP3 Online Free

Upload an MP3, WAV, M4A, OGG, or FLAC file. Adjust the playback speed from 0.5× to 2×, with or without pitch preservation. Download instantly. No signup, no watermark.

Drop an audio file here

or click to browse · max 50 MB · MP3, WAV, M4A, OGG, FLAC, AAC

Audio Speed Changer is a free browser-based tool for changing the playback speed of audio files without installing software. Upload an MP3, WAV, M4A, OGG, FLAC, or AAC file up to 50 MB, choose a speed between 0.5× and 2×, and download the result. Two modes cover the most common use cases: pitch-preserving speed change for podcasts and lectures, and natural speed-shift for creative effects.

Pitch preservation vs. natural speed-shift

With "Preserve pitch" enabled (the default), the tool uses FFmpeg's atempo filter to change the tempo of the audio while keeping every pitch at the original key. A podcast episode played at 1.5× sounds like the same voice speaking faster — not like a chipmunk. This is the mode used by every major podcast app, YouTube, and audiobook players.

With pitch preservation disabled, the tool applies a raw sample-rate change (asetrate). The result is the classic speed-pitch coupling: 2× speed raises all pitches by one octave and 0.5× lowers them by one octave. This mode is useful for creative effects — voice transformation, pitch-shifted instruments, or intentional speed-pitch coupling for music production experiments.

Speed range and presets

The slider covers 0.5× (half speed) to 2× (double speed) in steps of 0.05. Five preset chips — 0.5×, 0.75×, 1.25×, 1.5×, 2× — cover the most common use cases: 0.5× for detailed transcription, 0.75× for language learning, 1.25× for a modest podcast speedup, 1.5× for regular commute listening, and 2× for review or skim. The slider and preset chips are bidirectionally linked: clicking a chip snaps the slider; dragging the slider off a preset value deselects all chips.

Output format

The output uses the same container and format as the input. An MP3 input produces an MP3 output; a WAV produces a WAV. No format conversion is applied. The output filename reflects the speed applied — podcast_1.5x.mp3 — so you can keep multiple speed variants without confusion.

Common use cases

Speeding up a podcast for commute listening — A listener works through a 90-minute interview podcast during a 45-minute commute. At 2× with pitch preservation on, the episode fits exactly. The speaker's voice is recognizable and intelligible — the only difference is pace.
Slowing down a lecture for note-taking — A student is working through a recorded lecture on a complex topic. Playing at 0.75× gives them time to pause and write without constantly rewinding. The instructor's voice remains at the original pitch and accent, just slower.
Language learning at a reduced pace — A learner is working through an audio course in a second language. At 0.5× speed, each sentence plays at half pace, making it easier to catch individual words and reproduce the pronunciation. Once familiar, the speed is raised to 0.75× then 1×.
Reviewing a recorded meeting at 1.5× — A team lead needs to review a 60-minute recorded standup to pull out three action items. At 1.5× the review takes 40 minutes and the speakers are still comprehensible. They mark the timestamps and scrub back for the relevant sections.
Creative pitch-shift effect for music production — A music producer wants a pitched-down vocal sample for a lo-fi track. With preserve pitch off and speed set to 0.75×, the sample plays slower and a minor third lower — the classic tape-slow effect, without a dedicated pitch-shift plugin.

Frequently asked questions

Does changing speed affect the pitch?

With "Preserve pitch" on (the default), the pitch stays at the original key regardless of speed. Turn it off for a natural speed-shift effect — the audio sounds like a chipmunk at 2× or very deep at 0.5×.

What file formats are supported?

MP3, WAV, M4A, OGG, FLAC, and AAC — up to 50 MB and 20 minutes in duration. The output is delivered in the same format as the input. No conversion is applied.

Is there a file size or duration limit?

Files up to 50 MB and up to 20 minutes are supported. For longer recordings, consider trimming with AT USE Audio Trimmer first.

What speed range is available?

From 0.5× (half speed) to 2× (double speed) in increments of 0.05. Five quick-select preset chips are available: 0.5×, 0.75×, 1.25×, 1.5×, and 2×.

Is the audio processed on my device or on a server?

Processing is done on our server using FFmpeg. Your file is uploaded over HTTPS, processed, and automatically deleted after you download the result. No account required.

Keep going

More audio tools

Live Audio

Audio Trimmer

Cut or trim an MP3 or WAV file online. Set start and end times, download your clip instantly.

Open tool

Live Audio

Audio Volume Changer

Increase or decrease the volume of an MP3 or WAV file. Adjust by dB or normalize to LUFS.

Open tool

Live Audio

Audio Pitch Changer

Shift the pitch of an audio file by semitones without changing the tempo.

Open tool

Live Video

MP4 to MP3

Extract audio from a video file as MP3 instantly. Supports MP4, MOV, MKV, and WEBM.

Open tool