Audio Compressor

About Audio Compressor

This online audio compressor reduces the dynamic range of your audio, making loud parts quieter and quiet parts relatively louder. This creates more consistent, even audio that's easier to listen to and better suited for broadcasting, podcasting, and online content. Choose from professional presets or fine-tune advanced parameters for complete control.

What audio formats are supported?

Input: All common formats (MP3, WAV, OGG, AAC, M4A, FLAC, etc.). Output: MP3, WAV, OGG, or keep same format as input.

What is audio compression (dynamics)?

Audio compression (dynamics processing) reduces the difference between the loudest and quietest parts of audio. It makes loud sounds quieter while optionally boosting the overall level with makeup gain. This is different from file compression (making files smaller). Dynamic compression makes audio sound more consistent and controlled.

When should I use compression?

Use compression for: Podcasts and voice recordings (even out volume variations), Music production (control dynamics), Broadcasting (meet loudness standards), Videos and YouTube (consistent audio levels), Audiobooks (comfortable listening), Live streaming (prevent volume jumps).

What do the presets do?

Gentle: Subtle compression, natural sound. Moderate: Balanced compression for general use. Heavy: Strong compression, very even audio. Broadcast: Radio/TV standards. Podcast: Optimized for voice with natural feel. Choose based on your content type and how much control you want.

What is threshold?

Threshold (in dB) is the level above which compression starts. Audio louder than threshold gets compressed. -30 dB: light compression (only loud parts). -20 dB: moderate. -10 dB: only very loud peaks compressed. Lower threshold means more audio gets compressed.

What is ratio?

Ratio determines how much compression is applied above threshold. 2:1 (gentle): for every 2 dB above threshold, output increases 1 dB. 4:1 (moderate): standard compression. 8:1+ (heavy): strong compression, almost limiting. Higher ratio = more aggressive compression.

What are attack and release?

Attack: How quickly compression activates when audio exceeds threshold. Fast attack (1-5ms): catches transients, more controlled. Slow attack (10-30ms): lets transients through, punchier. Release: How quickly compression stops after audio drops below threshold. Fast release: responsive. Slow release: smoother, more natural.

What is knee?

Knee determines how gradually compression is applied around the threshold. Hard knee (0 dB): abrupt, precise compression at threshold. Soft knee (20-40 dB): gradual, smooth transition, more natural sounding. Soft knee is generally more musical.

What is makeup gain?

Makeup gain adds volume after compression to compensate for the loudness reduction. If compression makes audio quieter, makeup gain brings it back up. Typically 2-6 dB. This makes the compressed audio as loud or louder than the original while being more controlled.

Will compression affect quality?

Compression itself doesn't reduce audio quality (no data loss). However, over-compression can make audio sound unnatural, squashed, or fatiguing. Use gentle-moderate settings for most content. The output file format (MP3 vs WAV) affects quality more than compression.

What's the difference between this and audio normalization?

Normalization adjusts overall volume to a target level but doesn't reduce dynamic range. Compression reduces dynamic range (makes loud/quiet parts more similar) AND can increase overall loudness. Use normalization for simple volume adjustment, compression for controlling dynamics.

Is my audio file safe?

Yes! All processing happens locally in your browser using FFmpeg.wasm. Your audio file is never uploaded to any server. Everything stays private on your device.