Free Online Audio Speed Changer
Speed up or slow down audio from 0.25x to 3x while keeping the original pitch. 100% browser-based — no upload, no watermark, no signup.
Features
Change Speed, Keep Pitch
From 0.25x to 3x playback with voices that still sound natural — no chipmunk, no deep-demon effect.
9 Speed Presets
0.25x, 0.5x, 0.75x, 1x, 1.25x, 1.5x, 2x, 2.5x, 3x — one click each.
Pitch Preserved
Time-stretching via FFmpeg atempo filter keeps the original key and tone intact.
Instant Preview
Compare original and adjusted side-by-side before downloading.
Perfect for Learners, Podcasters, Musicians
Save hours on long episodes, catch every word in a foreign language, or slow down a tricky passage to learn it note by note.
Podcast Listeners
Speed up hour-long episodes to 1.5x or 2x — save time on every commute.
Language Learners
Slow foreign-language audio to 0.75x or 0.5x to hear every syllable clearly.
Music Practice
Slow a complex passage to 0.5x to learn the notes, then speed back up as you improve.
100% Private & Free
Audio stays on your device. All processing runs through FFmpeg WebAssembly locally.
No Server Upload
Files are never sent to any server — they stay on your device end-to-end.
Multiple Formats
Accepts MP3, WAV, AAC, OGG, FLAC, M4A and more. Export as MP3 or WAV.
Works Everywhere
Desktop, tablet, or phone — any modern browser handles it.
Loved by creators, students & researchers
Why people use BibiGPT to turn videos into text every day.
Trusted by 50,000+ users worldwide
“I paste a link and get clean captions in seconds — it saves me hours of retyping every single week.”
Maya R.
Content Creator · Repurposes short videos
“Exporting the transcript lets me review new words at my own pace instead of pausing the video constantly.”
Daniel K.
Language Learner · Studies with real videos
“Accurate, timestamped text I can quote directly. It has quietly become part of my daily workflow.”
Priya S.
Researcher · Cites public talks
FAQ'S
Frequently Asked Questions
Ask us anything!
Change Your Audio Speed Now
Free, private, and instant. Pick a speed preset and download in seconds — no signup required.