UT1 Time Calculator

Calculate UT1 (Universal Time) based on Earth's rotation. UT1 is derived from astronomical observations and differs from UTC by up to 0.9 seconds.

Results

UTC

Sat, 31 Jan 2026 00:08:56 GMT

UT1

Sat, 31 Jan 2026 00:08:56 UT1

DUT1

0.0000s

Julian Date

2461071.506204

MJD

61071.006204

Julian Century

0.260821525

Earth Rotation Parameters

Greenwich Mean Sidereal Time (GMST)

08:49:52.73

132.469728 degrees

Earth Rotation Angle (ERA)

132.135529 degrees

2.306200 radians

About UT1

UT1 (Universal Time 1) is a time scale based on the rotation of the Earth. Unlike UTC (which is based on atomic clocks), UT1 is determined by observations of distant celestial objects. The difference between UT1 and UTC is called DUT1.

DUT1 = UT1 - UTC, and is kept within +/- 0.9 seconds by adding leap seconds to UTC. The International Earth Rotation and Reference Systems Service (IERS) publishes DUT1 values regularly.