The approximate orbital altitude of the ISS is 400 kilometers above Earth. This places the station in low Earth orbit, where it circles the planet roughly every 93 minutes.
The ISS does not remain at one perfectly fixed height. Atmospheric drag gradually slows it, causing its orbit to decay by roughly 2 kilometers per month on average. Russian or visiting spacecraft periodically perform reboost maneuvers to raise the station again.
The station’s typical altitude has changed over its history. During the Space Shuttle era, NASA sometimes allowed the orbit to fall to make it easier for the shuttle to deliver heavy payloads. After the shuttle’s retirement, the nominal altitude was raised from about 350 kilometers to approximately 400 kilometers.
A common mix-up is confusing the ISS with geostationary satellites, which orbit about 35,786 kilometers above the equator. The ISS is far closer to Earth and travels much faster across the sky.