# What are the lower and upper hearing limits of the human ear?

I am looking for the loudness limits, expressed in decibels, for the human ear.

Google and Wikipedia is only giving me the frequency limit that the human ear can receive, but I cannot find mention about the decibel limits.

Related question on acoustic frequency: why-do-humans-hear-better-between-2khz-and-5khz

• Decibel limit for what? The lowest discernible sound? That depends on frequency, age of listener, etc. The level at which damage occurs? What kind of damage? The level at which deafness occurs? How quickly are you talking about? Seconds? Minutes? Instantaneously? Basically, please edit your question (don't respond in the comments) and clarify what exactly you're looking for. Otherwise, this question may be closed as "Too Broad" or "Unclear What You're Asking". Mar 19, 2015 at 2:04
• i am not asking in frequency limit, i want answer in decibels, db. Mar 19, 2015 at 2:07
• I edited your question to improve its clarity
– AliceD
Mar 19, 2015 at 2:38
• ok why you removed word decibel in the question. Mar 19, 2015 at 2:38
• sorry, thank you, for making my question more clear Mar 19, 2015 at 2:58

Hearing threshold is 0 dB SPL at 1 kHz, and pain threshold is around 125 dB SPL at that frequency.

Background
Loudness thresholds depend on acoustic frequency (pitch), as depicted in the following figure:

Loudness contours in human. Source: Stanford Uni

When expressed in dB sound pressure level (dB SPL) the threshold of pain is approximately 125 dB SPL. The lower bound peaks at a hearing threshold of about -5 dB SPL at 4 kHz (maximum sensitivity). Outside that frequency, hearing sensitivity declines (and threshold hence increases).

Note that dB SPL references to a sound pressure of 20 µPa = 2 × 10−5 Pa. This sound pressure corresponds to the hearing threshold at 1 kHz and is hence defined as 0 dB SPL. (Stanford Uni).