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Appliance Noise Frequency Identifier

What’s that hum, buzz, or whine? Point your microphone at the appliance, and this tool finds the dominant frequencies in the noise and suggests the likely source — mains hum, a compressor or motor, transformer buzz, or coil whine — with a live spectrum and the top tonal peaks.

🔎 This is a frequency-based heuristic, not a definitive diagnosis. Many appliances share frequencies, so treat the suggestion as a starting point. Get the mic close to the source and keep other noises quiet.

🔒 Runs entirely in your browser. No audio is recorded, uploaded, or stored.

Microphone

Idle — press Start, then hold the mic near the appliance.

Dominant tone

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Listening…

Top tonal peaks

FrequencyLevelLikely source
No clear tones yet — start listening near the noise.
A steady appliance hum shows one or two strong peaks (often at 50/60 Hz or 100/120 Hz, plus the mechanical tone). Coil whine appears high up (1–10 kHz). If everything is low and flat, it’s broadband noise with no single tone.
Live noise spectrum (log frequency) — detected peaks marked

Reading the Noise

Most annoying appliance noises are tonal — they sit at one pitch (a hum or whine) rather than a broad hiss. Every tone has a frequency, and many appliances produce characteristic frequencies, so measuring the pitch narrows down the cause. This tool captures your microphone, runs an FFT, and picks out the strongest narrow peaks, then matches the dominant one to a table of common sources.

The single most common culprit is mains hum: a tone at your country’s power-line frequency (60 Hz in the Americas, 50 Hz most elsewhere) and its harmonics (120 Hz / 100 Hz, etc.). It comes from transformers, power supplies, dimmers, and the electronics inside appliances. Mechanical noise — a fridge or AC compressor, a pump, a fan — tends to sit a bit higher (tens to a few hundred Hz). Coil whine from power supplies, GPUs and chargers is a high-pitched tone, often 1–10 kHz.

Rough frequency → likely source guide

  • 50 / 60 Hz — mains hum (transformer, PSU, ground loop, dimmer).
  • 100 / 120 Hz — mains 2nd harmonic; transformer/ballast core, fridge & AC electronics, fluorescent/LED drivers.
  • 20–120 Hz broadband — low rumble: HVAC, compressors, washing machines, large fans.
  • 120–400 Hz — compressor or motor hum (fridge, AC, pumps).
  • 400–1500 Hz — motor/fan whine, blade-pass tones, spinning drives.
  • 1.5–10 kHz — coil whine (PSU/GPU/charger), switching supplies, fan bearings.
  • ~15.7 kHz — old CRT TV/monitor flyback whine.

Why it’s only a guess

Frequency alone can’t uniquely identify an appliance — a 120 Hz tone could be a transformer, a fridge, or a fluorescent light. Room acoustics, your mic, and overlapping sources all blur things. Use the reading to narrow the search (e.g. "it’s electrical hum, not mechanical"), then confirm by switching appliances off one at a time and watching which peak disappears.

Frequently Asked Questions

How do I find which appliance is making the noise?
Start listening, note the dominant frequency, then switch suspect appliances off one at a time. When the peak on the spectrum drops, you’ve found the source. Getting the mic within a few centimeters of each candidate also makes its tone dominate, helping you isolate it.
It says "mains hum" — what does that mean?
A strong tone at 50 or 60 Hz (or 100/120 Hz) is electrical hum from the power line, common to transformers, power supplies, chargers, dimmers, and ground loops. It’s usually electrical rather than mechanical. If it’s coming through your audio gear, look at grounding and cabling; if it’s acoustic from a device, it’s often a transformer or ballast.
What is coil whine?
A high-pitched tone (commonly 1–10 kHz) from electronic components — inductors/coils in power supplies, GPUs, laptop chargers and LED drivers vibrating at their switching frequency. It’s usually harmless but annoying. This tool flags high-frequency tones as likely coil whine.
Why does the identification jump around?
If no single tone dominates, the strongest peak flickers between competing sources and background noise. Move the mic closer to the appliance you’re investigating and reduce other noise so one peak stands clearly above the rest.
Can it tell 50 Hz from 60 Hz?
Yes — it uses a high-resolution FFT, so 50 Hz and 60 Hz land on clearly separate frequencies. That distinction can even hint at region or a specific device (e.g. an imported transformer humming at the "wrong" mains frequency).
Is the suggestion definitive?
No. It’s a frequency-based heuristic — several appliances share frequencies, and the tool only sees the pitch, not the device. Treat it as a clue that points you in the right direction (electrical vs mechanical, low vs high), then confirm by elimination.
Does it disable noise suppression?
Yes — it requests the raw signal with noise suppression and auto-gain off, so steady appliance tones aren’t filtered out. If your OS forces noise suppression, it may remove exactly the hum you’re trying to find; disable microphone "enhancements" in system settings.
Is any audio recorded?
No. The signal is analyzed in real time to find tonal peaks only; nothing is recorded, saved, or transmitted. The microphone is released when you press Stop or close the tab.

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