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
Thu, 28 May 2026 22:36:42 GMT
UT1
Thu, 28 May 2026 22:36:42 UT1
DUT1
0.0000s
Julian Date
2461189.442153
MJD
61188.942153
Julian Century
0.264050435
Earth Rotation Parameters
Greenwich Mean Sidereal Time (GMST)
15:02:37.12
225.654653 degrees
Earth Rotation Angle (ERA)
225.316316 degrees
3.932512 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.
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Editorial Note
MyCalcBuddy Editorial Team
This page is maintained as an educational calculator reference.
Formula Source: Standard Mathematical References
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