Equalizer
Audio Processing LaboratoryShape the sound with a multi-band graphic equalizer.
What is Equalizer?
Equalizer lets you reshape the tone of an audio file with a five-band graphic EQ, right in your browser. Boost or cut each band by up to 12 dB across sub-bass, bass, low mids, presence, and air, then download the result. The filtering runs on the Web Audio API on your device, so your file is never uploaded.
How to use Equalizer
Add your audio
Drag an MP3, WAV, M4A, or OGG file onto the drop zone. The tool decodes it and shows a playable preview with its duration.
Adjust the five bands
Each slider covers a frequency range — 60 Hz (Sub), 230 Hz (Bass), 910 Hz (Low mid), 3.6 kHz (Presence), and 14 kHz (Air). Move any slider between -12 and +12 dB to cut or boost that band.
Dial in your curve
The dB value beside each band updates as you drag. Use Reset to flat to return every band to 0 dB and start again.
Apply and download
Click Apply EQ & download to render the audio through the filter chain and save it. Everything happens locally, so nothing is uploaded.
Common uses
- Add warmth by boosting the bass on a thin recording
- Tame harsh, sibilant highs by cutting the air band
- Bring a voice forward by lifting the presence band
- Reduce boominess by trimming the sub-bass
- Add clarity to a muddy mix by shaping the low mids
- Brighten a dull podcast or lecture recording
Why choose FreeTools
100% private
Your files are processed inside your browser and are never uploaded to a server.
Free, no account
No sign-up, no watermark, no paywalled “premium” tier. Just open a tool and use it.
Instant
No upload, no queue, no server round-trip — work starts the moment you drop a file.
Runs in your browser
Built on open web standards. Works on any modern desktop browser, nothing to install.
No upload size caps
Nothing leaves your device, so there’s no server file-size limit — only your machine’s memory.
Yours to keep
Results download straight to your device in clean, standard file formats.