How loud is a sperm whale?
Sperm whale echolocation clicks reach source levels of up to 236 dB re 1 µPa (rms) at 1 m, measured on the axis of the beam by Møhl and colleagues in 2003. That makes them the loudest sounds recorded from any animal; Guinness World Records lists them as the loudest animal sound.
- Level
- 236 dB re 1 µPadecibels relative to 1 micropascal, measured in water
- Distance
- 1 m1 m (source level, back-calculated, on the axis of the click)
- Daily limit
- Underwater levelnot an air level
What the numbers mean
How it was measured. Underwater level in dB re 1 µPa. Underwater decibels are not comparable with in-air decibels: see "underwater-vs-air". Source level up to 236 dB re 1 µPa (rms) for on-axis clicks recorded off Vesterålen, Norway, in July 2000 (Møhl et al. 2003).
Bertel Møhl's team recorded sperm whales in the Bleik Canyon off Vesterålen, Norway, in July 2000 with a wide, GPS-synchronised hydrophone array. Clicks that hit the array head-on were monopulsed, lasted about 100 microseconds, had centroid frequencies around 15 kHz and reached source levels up to 236 dB re 1 µPa (rms). The authors wrote that this makes sperm whale clicks by far the loudest sounds recorded from any biological source.
The clicks are highly directional, with a composite directionality index of 27 dB, so earlier off-axis recordings had made them seem weaker and longer. Their job is long-range biosonar. Guinness World Records lists the clicks as the loudest sound made by an animal and notes that sperm whales can hear one another tens of kilometres away.
236 dB underwater is not 236 dB in air. Underwater decibels use a 1 µPa reference and water carries sound differently, so DOSITS advises subtracting 61.5 dB to compare equal intensities in air.
Is it dangerous?
Measured in water against a 1 µPa reference, so the number cannot be compared directly with levels in air. See the underwater note on the Scroll. Marine-mammal and diver exposure criteria use their own metrics and are outside the scope of this page.
Protecting your hearing
Not a practical risk to swimmers or divers; the beam is narrow and sperm whales hunt in deep water.
Questions
What is the loudest animal on Earth?
The sperm whale. Its echolocation clicks reach source levels of up to 236 dB re 1 µPa at 1 m, the loudest sounds recorded from any animal.
Could a sperm whale's click hurt a human?
The record figure applies at 1 m on the axis of a narrow beam, in deep water. Underwater decibels are also not comparable with air decibels, so 236 dB here does not mean 236 dB to your ears.
Sources
- The monopulsed nature of sperm whale clicks, Journal of the Acoustical Society of America (Møhl et al., 2003) via PubMed. Supports: 236 dB re 1 µPa (rms).
with source levels up to 236 dB re: 1 microPa (rms)
Checked 2026-11-02. - The monopulsed nature of sperm whale clicks, Journal of the Acoustical Society of America (Møhl et al., 2003) via PubMed. Supports: Loudest biological source.
The sound levels measured make sperm whale clicks by far the loudest of sounds recorded from any biological source
Checked 2026-11-02. - Loudest animal sound, Guinness World Records. Supports: Record listing, 236 dB.
These clicks can be as powerful as 236 decibels (dB)
Checked 2026-11-02.
This page is general information, not medical advice. If you have ringing in your ears, muffled hearing or any change in your hearing, see an audiologist or your doctor.