Mosquito Tone Test 17.4 kHz — Free

The mosquito tone test plays the 17.4 kHz classic tone and eleven other high-frequency presets from 8 kHz to 22 kHz so you can hear the premise for yourself. Tones are generated locally with the Web Audio API, nothing is recorded, and the page is built as a safe demo rather than a scientific test of age.

How to use it

1. Turn your system volume down before pressing anything. High-frequency tones can sound piercing at levels that feel modest, and an unheard tone still carries acoustic energy.
2. Pick a preset, starting with 8 kHz. The featured button is the 17.4 kHz classic Teen Buzz figure; the rest of the row runs 8, 10, 12, 14, 15, 16, 18, 19, 20, 21 and 22 kHz.
3. Press Play 800ms Safe Pulse. The pulse is an 800 ms sine with a 30 ms attack and release, and the gain slider is clamped between 0.02 and 0.25, roughly -34 dBFS to -12 dBFS. Continuous Tone is available for a longer listen.
4. Answer I Heard It or Silence / Inaudible. The checklist records frequency, the page’s reference age band and your result, and Clear empties the table.
5. Work along the row at one fixed volume. A tone that appears only after you raise the slider tells you about the slider, not about your ear.
6. Keep pets out of the room and stop at any discomfort. Dogs and cats hear far above 20 kHz, and the 20-22 kHz presets sit outside most adults’ range on any gear.
7. Re-run the same preset on a second device before concluding anything. A silent 17.4 kHz chip on a laptop is usually the speaker’s fault, so compare with wired headphones elsewhere.

The 17.4 kHz premise

The 17.4 kHz figure comes from a real commercial device: a high-frequency youth deterrent developed by Howard Stapleton, launched in 2005 through Compound Security Systems and widely reported as audible mainly to people under about 25.

BBC News reported in 2008 that the device emitted a tone between 17.5 kHz and 18.5 kHz, and that the Mark 4 version added an all-age 8 kHz setting after criticism that the original targeted only young people. The commonly cited 17.4 kHz figure matches the manufacturer’s teenage-only setting on later versions, and the idea spread as the Teen Buzz ringtone. The premise describes a population tendency: sensitivity above roughly 16 kHz declines with age on average, but individual variation is large, so some teenagers cannot hear 17.4 kHz and some adults in their forties can. Its use was contentious, with UK councils and children’s commissioners campaigning against it. This page reproduces the tone for demonstration and makes no claim about your age or hearing health.

What actually happens to a 17.4 kHz tone

A browser oscillator can render 17.4 kHz exactly, but the tone still has to survive the sample rate, the codec, the amplifier and a speaker whose dimensions are comparable to the wavelength.

Sample rates set the first ceiling: 44.1 kHz playback reaches a 22.05 kHz Nyquist limit, 48 kHz reaches 24 kHz, and a device that resamples internally to 32 kHz stops at 16 kHz. Lossy codecs add a second: ordinary MP3 and AAC bitrates commonly band-limit near 16 kHz, so a streamed clip may contain nothing at 17.4 kHz. Then the speaker beams the tone, because the wavelength at 17.4 kHz is about 19.7 mm (λ = 343 / f at 20 °C), so a centimetre of angle or distance can drop the level sharply.

Frequency	Wavelength at 20 °C	Typical limitation
8 kHz	42.9 mm	Speaker quality; almost all adults hear it
12 kHz	28.6 mm	Tweeter response and lossy codecs start to matter
16 kHz	21.4 mm	Common lossy-codec limit at ordinary bitrates
17.4 kHz	19.7 mm	Codec limit, speaker response and beaming combine
20 kHz	17.2 mm	Top of the nominal hearing range; many adults and devices cannot reach it
22 kHz	15.6 mm	Above most adults’ hearing and beyond many drivers

Volume, safety and what this is not

High-frequency energy is real energy: a silent 22 kHz tone still heats a tweeter, so the volume limiter and the 800 ms pulse are deliberate.

The gain cap keeps the source near -12 dBFS at maximum, but system volume still sets the acoustic level, so keep it low, stop if a tone feels sharp, and never raise the volume to chase one. This page is not a medical test or diagnosis: a missed tone is not evidence of hearing loss, and hearing a tone is not proof of youth. The reference age bands beside each preset are population shorthand from the device’s history, not measurements of you. If you are concerned about your hearing, or notice one-sided or sudden changes, see an audiologist or clinician.

Accuracy, limits and troubleshooting

Hardware explains most surprises on this page, not the oscillator.

• dBFS only. The gain slider is a digital level, not a calibrated acoustic one, so the same setting is loud on one device and faint on another.
• Two devices tell the truth. If 17.4 kHz is silent on a laptop but clear on wired headphones, the laptop was the limit.
• The log is session-only. Nothing persists after reload and nothing is uploaded, so note anything you want to keep.
• 21 kHz and 22 kHz are usually silent. Many drivers do not reproduce them and most adults cannot hear them, so treat the top of the row as a hardware check.
• Browsers need a gesture. If Play does nothing, click once in the page; in-app browsers can block Web Audio.

Related tools

• Hearing Age Test — A full preset walk with listening-age framing instead of a single classic tone.
• High-Frequency Hearing Test — Map heard and not-heard tones from 8 kHz to 22 kHz with a saved result.
• Online Hearing Test — Per-ear screening from 125 Hz to 8 kHz if you want a broader check.