How dark is the night sky where you live?

3,206 US cities. Start typing yours.

Satellite radiance readings for 3,206 US cities, turned into a brightness band and a distance to the nearest darker sky, not a national average standing in for your town.

The six bands this site measures

Band	Example city	Radiance	What it looks like
Dark sky	Hardeeville, SC	1.4	Among the darkest skies of any US city in this dataset. The Milky Way should be visible overhead on clear, moonless nights.
Rural	Sylacauga, AL	5.2	Little local light dome. Most stars are visible; the Milky Way is faint but often findable away from town lights.
Suburban edge	Ingleside, TX	14.7	A noticeable glow near the horizon. Brighter stars and constellations are easy to pick out; the Milky Way is washed out.
Suburban	Elk Grove, CA	28.7	Light dome dominates much of the sky. Only the brightest stars and planets stand out clearly.
Urban	Cambridge, MA	55.0	Sky glow overhead most nights. Typically only planets, the Moon, and a handful of the brightest stars are visible.
Inner-city	Addison, TX	105.3	Among the brightest skies in this dataset. Usually just the Moon and a few of the brightest stars or planets cut through.

Where 3,206 US cities fall: 85 dark sky, 335 rural, 995 suburban edge, 1324 suburban, 421 urban, 46 inner-city.

Browse all 3,206 cities by state

What this measures, and what it does not

DarkSkyCheck turns NOAA's VIIRS satellite radiance data into a brightness band for 3,206 US cities, covering 51 states and roughly 186,164,571 people. It is not a Bortle class, Bortle is a ground observation and this is a measurement from orbit, but the two track closely enough to say whether a backyard sky is worth using or worth leaving.

The one thing every city page adds beyond a lookup

Knowing your own sky is dim is only half the question, the other half is where a darker one actually is. Every city page also names the nearest city in this dataset with a meaningfully darker sky and the straight-line distance to it, real driving distance will run longer.