🦗 Crickets Chirping Thermometer
Count how many times a cricket chirps and estimate the outdoor temperature using the classic Dolbear’s Law formula.
The cricket thermometer
Crickets are cold-blooded, so their metabolism — and how fast they chirp — speeds up as the air warms. This relationship was formalized in 1897 by physicist Amos Dolbear as Dolbear’s Law, originally based on the snowy tree cricket.
The formula
Dolbear’s Law estimates temperature in Fahrenheit as: T = 50 + (N – 40) / 4, where N is the number of chirps counted in one full minute. A handy shortcut version of the same idea, popularized by almanacs, is to count chirps for just 14 seconds and add 40 to get an approximate Fahrenheit temperature.
This is a fun, reasonably accurate approximation rather than a precise instrument reading — species, cricket age, and health all affect chirp rate somewhat. Use it for general outdoor curiosity rather than as a substitute for an actual thermometer.