Requires microphone access. Audio is analyzed locally in your browser - nothing is recorded or uploaded. Browser echo cancellation and noise suppression are disabled for a truthful spectrum.
Hunt down hums
A persistent spike at 50 or 60 Hz is mains hum; at 100/120 Hz, its first harmonic - usually a ground loop or transformer. Broadband low rumble points at HVAC or traffic. The peak readout names the frequency for you.
Verify test signals
Play a tone from our tone generator on another device and confirm the spike lands at the expected frequency - or run pink noise through speakers and eyeball the room's response shape.
See voices & instruments
Sing or play a note: the tallest low spike is the fundamental, the evenly spaced spikes above it are harmonics - the recipe that makes your voice yours. Whistle for the purest single spike you can produce.
Spectrum Analyzer FAQ
What does a spectrum analyzer show?
It splits incoming sound into its frequency components and displays how much energy is present at each frequency, updated many times per second. A pure tone shows as a single spike; a voice shows a fundamental plus harmonics; noise shows a broad wash. The height of each bar is relative level in that frequency band.
Why does the analyzer need my microphone?
The analyzer visualizes real sound from the room, which requires microphone access. Everything runs locally in your browser using the Web Audio API - no audio is recorded, stored, or sent anywhere, and access stops the moment you press Stop or leave the page.
How accurate is a browser spectrum analyzer?
Frequency readout is accurate to within a few hertz (limited by FFT resolution, about 23 Hz per bin at the default settings). Absolute level is not calibrated - your microphone, its position, and browser processing all shape it - so treat levels as relative. For frequency identification (finding a hum, checking a tone, spotting harmonics) it is genuinely reliable.
What can I use a spectrum analyzer for?
Identifying mystery noises (a 50/60 Hz spike means mains hum, 100/120 Hz its harmonic), checking what frequencies dominate a room, verifying a test tone is playing at the right frequency, watching your voice or instrument harmonics, and roughly assessing speaker output across the band when playing pink noise or a sweep through them.
Why do I see activity even when the room is silent?
Microphone self-noise and room ambience never reach zero, and browsers may apply automatic gain that amplifies quiet backgrounds. A low broadband floor is normal. Distinct persistent spikes in a "silent" room are real signals worth investigating - commonly HVAC rumble at low frequencies or electronic whine higher up.
Try Our Other Audio Tools
Online Tone Generator
Generate single tones with precise frequency control. Perfect for quick audio testing and tuning.
Multiple Tone Generator
Play multiple frequencies simultaneously with independent volume and panning controls.
Frequency Sweep Generator
Create linear or exponential frequency sweeps for speaker testing and room acoustics analysis.
Binaural Beats Generator
Generate binaural beats for meditation, focus, and relaxation. Requires headphones for proper effect.
DTMF Tone Generator
Generate telephone dial pad tones (Dual Tone Multi Frequency). Interactive touch-tone dial pad.
Online Metronome
Professional metronome with tap tempo, time signatures, subdivisions, and tempo trainer for musicians.
BPM Counter
Tap along to any song to find its tempo in beats per minute. Includes tempo markings reference.
Chord Player
Hear major, minor, diminished, and seventh chords in every key. Block chords or arpeggios.
Noise Generator
Generate white, pink, and brown noise for sleep, focus, tinnitus relief, and speaker burn-in.
Instrument Tuner
Reference tuning notes for guitar, bass, ukulele, violin, cello, and more at concert pitch (A440).
Subwoofer Test
Test your subwoofer with a 60-second frequency sweep (150Hz-1Hz) and individual bass test tones.
Hearing Test
Test your hearing range from 8kHz to 20kHz. Find your hearing age and compare with averages.
Solfeggio Frequencies
Ancient healing tones including 528Hz (DNA repair). For meditation, chakra activation, and spiritual healing.
Speaker Balance Test
Test stereo balance with panning control and left/right channel testing. Perfect for speaker setup.
Speaker Phase Test
Check speaker wiring polarity by comparing in-phase and out-of-phase test signals.
Audio Latency Test
Measure your Bluetooth or system audio delay in milliseconds with a click-and-flash sync test.
Interval Ear Trainer
Learn to recognize musical intervals by ear with quiz mode, score tracking, and song mnemonics.
Pitch Pipe
Chromatic pitch pipe with all 12 notes across 3 octaves. Perfect for singers, choirs, and a cappella groups.
Shepard Tone
Experience the auditory illusion of an infinitely ascending or descending tone. Mind-bending psychoacoustic phenomenon.
Mosquito Tone
Can you hear the mosquito tone? High-frequency test (15-20kHz) that only young people can hear. Find your hearing age!
Soundscape Builder
Create relaxing ambient soundscapes with singing bowls, nature sounds, and binaural beats.