Audio Speed Changer

Changing audio speed (tempo) without affecting pitch is called time-stretching. This tool uses FFmpeg's atempo filter which preserves pitch while changing tempo — so voices and instruments sound natural at different speeds. Popular use cases: listening to long podcasts or audiobooks at 1.5× or 2× to save time; slowing down music to 0.5× or 0.75× to learn guitar riffs, piano pieces, or song lyrics; creating slow-motion audio effects for video production. The atempo filter supports 0.5× to 2.0× natively; speeds outside this range are achieved by chaining multiple atempo filters. Output is always MP3 for maximum compatibility.