Audio dynamics compressor
Even out the loud and quiet parts of a recording with threshold, ratio, knee, attack and release controls, and see the gain reduction over time. This changes the dynamics of the sound, not the size of the file.
Accepted files: .wav,.mp3,.m4a,.aac,.flac,.ogg,.oga,.opus,.webm,audio/*. Choose one file. Up to 256 MiB in total.
One recording up to 256 MiB and 10 minutes; threshold -60 to 0 dBFS, ratio 1 to 20, knee 0 to 24 dB, attack 0.1 to 200 ms, release 5 to 2,000 ms, makeup 0 to 24 dB. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV gain reduction trace. The dynamics of this file are compressed; its size is not reduced. Up to 1,000,000 characters. Review the settings before running.
Your result
How to use Audio dynamics compressor
- Choose the recording to compress.
- Set the threshold, ratio and knee, then the attack and release times.
- Add makeup gain if you want the result louder.
- Compress, compare the original and processed sound, check the gain reduction trace, and download the WAV.
Useful next steps
One recording up to 256 MiB and 10 minutes; threshold -60 to 0 dBFS, ratio 1 to 20, knee 0 to 24 dB, attack 0.1 to 200 ms, release 5 to 2,000 ms, makeup 0 to 24 dB. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose, a JSON report and a CSV gain reduction trace.
Dynamics, not file size
A dynamics compressor turns down the parts of a recording that go above the threshold, so loud and quiet passages sit closer together. It does not make the file smaller. To reduce the file size, use the Compress audio tool instead.
How the gain is computed
The level of each sample is measured as a peak, or as an RMS level smoothed over 10 ms. Above the threshold the level is reduced by the ratio, so 4 to 1 lets 4 dB of input become 1 dB. The knee softens the change around the threshold, following the gain computer of Giannoulis, Massberg and Reiss (2012). Attack and release set how fast the reduction starts and ends.
Reading the result
The chart shows gain reduction over time. The full CSV lists the strongest reduction in each 10 ms step, and the report gives loudness and peaks before and after. Use loudness matching in the player to compare without making the louder version seem better. This changes playback only, not your download.