Spectrum Analyser

Overview

Watch the frequencies in your microphone or an audio file, live. The bars sit on a log axis so the low end gets room, and a slow peak hold lets you read short sounds that would otherwise vanish before your eye catches them. The microphone only opens when you ask, and audio never plays back through your speakers, so there's no feedback. Nothing is recorded or uploaded.

Check a roomSee which frequencies a space emphasises by playing pink noise and watching the curve.
Set up a PAWatch the balance while you ring out a system.
Look at an instrumentSee where a voice or instrument really sits.

Set

Audio Tools 17

Neighbours

01 Audio Transcriber 02 Generate AI Music 03 Audio Converter 04 BPM Detector 05 DJ Booth 06 Extract Audio from Video

Specification

Command: audio.spectrum_analyzer
Set: Audio
Input: MIXED
Output: —
Max file: 1GB
Batch: single file

MPEG WAV FLAC MP4 OGG OPUS AAC WEBM

Runtime

Engine: ffmpeg-wasm 0.12
Threads: — workers
Isolated: —
WebGPU: —
Memory: —

Transport 0 B

Your file is opened, worked on and saved inside this tab. This tool has no upload step, so your file has nowhere else to go.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/

How it works

Choose a source

Tap Use microphone, or drop an audio file. The browser only asks for the microphone when you press the button.

Watch the balance

Bars show the spectrum right now. The thin line above each bar is the peak hold.

Read the axis

Frequency runs logarithmically from 20 Hz to 20 kHz.

Frequently asked

Does this record anything?

No. Each frame is analysed and thrown away. Nothing is stored, and nothing is sent anywhere.

Why does it ask for microphone permission?

Only when you press the button, never on page load. If you'd rather not allow it, drop a file instead and you get the same display.

Are the levels calibrated?

No, and no browser tool can be, because the reading depends on your microphone and its gain. It shows the balance between frequencies, not absolute sound pressure. For SPL you need a calibrated meter.

Why is echo cancellation turned off?

Echo cancellation is a processor, so a spectrum read through it would show the processor, not the sound. Noise suppression and automatic gain are off for the same reason.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/