How to calculate the temperature by counting cricket chirps

Yes, I know it’s easier to just look at a thermometer, the weather app on your smartphone or the evening TV forecast.

And that you can probably just gauge the approximate temperature outside just based on how it feels. At the very least, you can narrow it down to one of the functionally sufficient — albeit unscientific — options of “comfortable,” “chilly,” “too hot” or “frigid.”

So consider this cricket temperature calculation a neat trick, or something to use if you’re out camping and don’t feel like using up phone batteries or data to get the temperature.

Using something known as Dolbear’s Law — named for the late 19th century academic A.E. Dolbear, who discovered this correlation — you can determine the temperature by counting cricket chirps.

Dolbear found that crickets chirp faster when the temperatures increase and slower when they decrease.

There are a couple of ways to figure out the temperature by counting chirps. Perhaps the simplest is the formula touted by The Old Farmer’s Almanac, which claims you can count the number of a cricket’s chirps in 14 seconds, and then just add 40 to reach the Fahrenheit temperature.

So if Jiminy chirps 28 times in 14 seconds, it’s about 68 degrees out.

The Library of Congress offers a slightly different approach, saying to count the number of a cricket’s chirps in 15 seconds and add 37.

So if Jiminy chirps at about the same approximate rate as in the previous calculation — two chirps per second — you’d get an answer of about 67 degrees.

Yet another researcher found the results to be most accurate when you count the number of chirps in 13 seconds and add 40. Jiminy would be telling us in the above scenario it’s 66 degrees out, using that approach.

The results are within two degrees of each other, in any case. Pretty close. Of course, different species of crickets chirp at slightly different speeds, so there are some variables based on where you live and what crickets are around.

(The snowy tree cricket seems to follow the above formulas most accurately and they do live in Maine. The more common field cricket, however, chirps a bit more slowly.)

If you think the cricket thing is neat, but don’t want to expend the brain power to add numbers together, you can find an online calculator, add in the number of chirps you hear in five seconds (as well as the season) and it’ll spit back out the approximate temperature.

Of course, if you’re on your computer, you might as well just Google the weather forecast. Kind of takes the fun out of it.

One last thing: When the temperatures fall below about 55 degrees, crickets get too cold to chirp with any vigor, so this game really only works from the late spring through the early fall.