Real audio processing, not a black box
A recording made with a phone or a basic microphone often carries a constant low hum, background hiss, and inconsistent volume between quiet and loud moments. This tool applies three genuine, well-established audio engineering techniques — directly inside your browser — to clean that up: a filter to remove low-frequency rumble, a noise gate to quiet background hiss between sounds, and normalization to even out the overall volume.
How it works
- Choose an audio file. Drag one in or tap to select it from your device.
- Set the noise reduction strength. Higher values gate down quiet background noise more aggressively.
- Enhance and compare. Listen to the original and processed versions side by side before downloading.
What's actually happening, technically
The audio first passes through a high-pass filter, which removes frequencies below about 90Hz — this is where most rumble, handling noise, and electrical hum tend to live, well below the range of most speech and music. It then passes through a compressor, which reduces the gap between the loudest and quietest parts of the recording. Finally, a noise gate — a technique that reduces volume when the signal drops below a set threshold, with a fast attack and a slow release to avoid audible clicks — quiets down the background noise that's audible during pauses, without cutting off the actual sounds you want to keep.
Getting the best result
This tool works best on recordings where the unwanted noise is a fairly constant, quiet hum or hiss — a room's air conditioning, a phone's built-in microphone noise floor, a slight electrical hum. It's less effective against noise happening at the same volume and time as the sound you want to keep, since a gate can only reduce volume during quiet moments, not separate two overlapping sounds. Starting with a moderate strength setting and adjusting from there usually gives the most natural-sounding result.
Nothing you upload here is stored
Because all processing happens locally, this tool never sees or stores the audio you use here. See our Privacy Policy for full details.
Frequently asked questions
+Is this audio enhancer really free, with no sign up?
Yes. There's no account and no limit on how many files you can process.
+Do you upload my audio to a server?
No. Every step — filtering, noise reduction, and volume normalization — runs directly in your browser using the Web Audio API. Your recording is never sent anywhere.
+What does this actually do to my audio?
Three things: a high-pass filter removes low-frequency rumble and hum below about 90Hz, a noise gate reduces the volume of quiet background hiss between sounds (without cutting off the sounds themselves), and an optional normalization step brings the overall volume up to a consistent, louder level.
+Will this remove noise that's happening at the same time as speech?
Not fully — this tool is a noise gate, not a source-separation AI. It's very effective at cleaning up quiet moments between words or sounds (room tone, background hum, hiss), but noise happening at the exact same time as speech (like a fan running constantly underneath someone talking) will still be present, just at a somewhat reduced overall level thanks to the compressor stage.
+What file format do I get back?
A WAV file — uncompressed and lossless, so no additional quality is lost during processing. If you need a smaller compressed file afterward, the site's Audio Converter can convert it to MP3 or another format.
+Why does higher noise reduction strength sometimes sound choppy?
Pushing the strength very high can make quiet transitions more noticeable, since more of the signal is being gated down. If a result sounds unnatural, try a lower strength setting — often somewhere in the 40–60% range gives the best balance between noise reduction and natural-sounding audio.