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NIST USNO
UTC (USNO) - UTC (NIST)
The United States Naval Observatory (USNO) and the National Institute of Standards and Technology (NIST) make regular comparisons of their respective time scales. These comparisons are made using GPS common-view measurements from up to approximately 10 GPS satellites. The table below lists recent differences between the two time scales.
Weekly UTC(USNO, Master Clock) - UTC(NIST)Values
| Date | MJD | UTC(USNO) - UTC(NIST) (+/- 5 ns) |
|---|---|---|
| 2025-07-28 | 60884 | -1.0 ns |
| 2025-07-23 | 60879 | -0.7 ns |
| 2025-07-18 | 60874 | -0.1 ns |
| 2025-07-13 | 60869 | 0.3 ns |
| 2025-07-08 | 60864 | 0.0 ns |
| 2025-07-03 | 60859 | 0.1 ns |
| 2025-06-28 | 60854 | -1.5 ns |
| 2025-06-23 | 60849 | -2.2 ns |
| 2025-06-18 | 60844 | -2.3 ns |
| 2025-06-13 | 60839 | -2.0 ns |
| 2025-06-08 | 60834 | -2.2 ns |
| 2025-06-03 | 60829 | -1.2 ns |
| 2025-05-29 | 60824 | -1.3 ns |
| 2025-05-24 | 60819 | -0.1 ns |
| 2025-05-19 | 60814 | 0.5 ns |
| 2025-05-14 | 60809 | 0.5 ns |
| 2025-05-09 | 60804 | 0.7 ns |
| 2025-05-04 | 60799 | 0.1 ns |
| 2025-04-29 | 60794 | -0.5 ns |
| 2025-04-24 | 60789 | -0.7 ns |
| 2025-04-19 | 60784 | -0.1 ns |
| 2025-04-14 | 60779 | -2.0 ns |
| 2025-04-09 | 60774 | -1.3 ns |
| 2025-04-04 | 60769 | -1.5 ns |
| 2025-03-30 | 60764 | -1.7 ns |
| 2025-03-25 | 60759 | -1.0 ns |
| 2025-03-20 | 60754 | -2.0 ns |
| 2025-03-15 | 60749 | -1.8 ns |
| 2025-03-10 | 60744 | -2.0 ns |
| 2025-03-05 | 60739 | -1.5 ns |
| 2025-02-28 | 60734 | -1.4 ns |
| 2025-02-23 | 60729 | -0.8 ns |
| 2025-02-18 | 60724 | -0.9 ns |
| 2025-02-13 | 60719 | -1.1 ns |
| 2025-02-08 | 60714 | 0.7 ns |
| 2025-02-03 | 60709 | -0.1 ns |
| 2025-01-29 | 60704 | -0.1 ns |
| 2025-01-24 | 60699 | 0.3 ns |
| 2025-01-19 | 60694 | 0.2 ns |
| 2025-01-14 | 60689 | 1.3 ns |
| 2025-01-09 | 60684 | 1.0 ns |
| 2025-01-04 | 60679 | 0.6 ns |
Created September 18, 2009, Updated September 8, 2025