Astronomical & Calendar Metadata
Today's Date & Chronology
Instantaneous metrics for the current day: ordinal day of year, ISO week index, Gregorian quarter, days remaining, Julian date, and atomic Unix epoch seconds.
ISO-8601 Calendar Spec
Continuous Julian Day
Real-Time Progress Metrics
Chronometry Calendar Overview
Thursday, September 17, 2026
5:04:50 PM
Year Progress (2026)71% Completed
Day 260 of 365 • 105 days remaining in 2026
Day of Year
Day 260ISO Week Number
Week 38Quarter of Year
Q3Leap Year Status
Common Year (365 days)Unix Timestamp
1789664690Julian Date (JD)
2461301.2117Days in Current Month
30 DaysCalendar Era
CE / ADFrequently Asked Questions About Today's Calendar Data
Learn how day ordinality, ISO weeks, and astronomical Julian dates are computed.
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Under the international ISO-8601 standard, weeks begin on Monday and are numbered from 1 to 52 (or 53). Week 1 is defined as the first week of the year with at least four days in the new calendar year (containing the first Thursday of January).
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