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Tempo Changer.

Slow a track for practice or speed it up for a mix with time stretching that aims to preserve pitch. Extreme changes can add artifacts.

Before-and-after illustration of Tempo Changer: Original tempo track becomes Tempo-adjusted audio through Stretch without repitch.
Before → process → afterSee the signal story, then hear it in the workspace.

TIMELINE MAP

Tempo Stretch Timeline

Turn one long waveform into deliberate boundaries. The visual emphasizes the selection, transition and resulting edit so that timing decisions remain obvious before anything is rendered.

Before-and-after illustration of Tempo Changer: Original tempo track becomes Tempo-adjusted audio through Stretch without repitch.
Original tempo trackStretch without repitchTempo-adjusted audio
A timeline edit: marked regions, handles and transitions resolve into clean finite segments without hiding where each boundary came from.
Open the full signal breakdownBest source, processing logic, limits and three-pass listening check
  1. Original tempo track

    Start with the right material

    Slowing a difficult passage for practice or testing a faster arrangement.

  2. Stretch without repitch

    Understand the transformation

    Overlap-add time scaling changes timing without simple resampling.

  3. Tempo-adjusted audio

    Verify the usable result

    A longer or shorter render whose pitch stays closer to the source.

New duration

Where this workflow stops

Extreme changes can smear attacks and produce phase artifacts. It does not analyze bars, beats or tempo maps.

THREE-PASS CHECK

Make the final decision by ear

  • Zoom into every boundary and listen across it, not only inside it.
  • Leave intentional handles when another editor will continue the work.
  • Verify exact duration and ordering after the final render.

How to change tempo without changing pitch

  1. Drop your track into the upload box — the original loads with a preview player.
  2. Pick a preset (75% Practice, 100%, 125%, 150%) or set any speed from 50% to 200% on the slider; the estimated output length updates as you move it.
  3. Press Change tempo and give the time stretch a few seconds to run.
  4. Preview the result — same key, new speed — and download MP3 or WAV.

A tempo changer is different from a simple speed control: instead of playing the file faster or slower (which drags the pitch along with it), it stretches time while leaving frequency alone. Chords stay in the same key, vocals keep their character, and only the pacing changes. That makes it the right tool for musicians slowing difficult passages, dancers rehearsing choreography at reduced speed, and anyone speeding through lectures and podcasts without chipmunk voices.

Processing stays in the browser with a 200 MB input cap; practical duration and render time depend on available memory and device performance. Use Nightcore or Slowed + Reverb when pitch and speed should move together, or Pitch Shifter when tempo should remain near its original duration.

Tempo Changer: quick answer and technical limits

Quick answer: A time-stretch tool that changes duration from roughly 50 to 200 percent speed while aiming to preserve musical pitch.

Best for
Slowing a difficult passage for practice or testing a faster arrangement.
How it works
Overlap-add time scaling changes timing without simple resampling.
What you get
A longer or shorter render whose pitch stays closer to the source.

Know before you use it: Extreme changes can smear attacks and produce phase artifacts. It does not analyze bars, beats or tempo maps.

Privacy: Selected audio is processed in this browser and is not uploaded to AudioWrench. Normal page assets can still be requested as described in the privacy notice. Privacy details →

FAQ

How can I change a song's speed while preserving pitch?
Use time stretching instead of simple playback-rate change. This tool rebuilds the waveform at 50%–200% tempo while aiming to preserve pitch. Large changes or transient-heavy audio can produce artifacts, so preview before export.
What speed is best for practicing an instrument along to a track?
Most players start at 75% — slow enough to read fast passages, fast enough to keep the feel — which is why it is a one-click preset here. Drop further to 50–60% for transcribing solos, then raise the tempo in steps as the part becomes comfortable.
Why does the tempo change take a few seconds to process?
Pitch-preserving stretching is real signal processing, not just faster playback, and it runs on your own device rather than a server. Expect a few seconds for a full song; the page shows the estimated output length before you commit.
Is the tempo changer free, and does my file stay private?
Yes — free, with no signup or watermark. The selected audio is processed on your device and is not uploaded to AudioWrench; normal page assets can still be requested as described in the privacy notice. When it sounds right you download the stretched version as a 320 kbps MP3 or WAV.