Date & Time
Calendar age, date differences, business days, average durations, and time arithmetic for planning and scheduling.
Use these calculators for calendar age, elapsed dates, business-day counting, duration averages, and time arithmetic. All date tools use UTC calendar normalization to avoid timezone drift. Business-day tools support optional US federal holiday exclusion.
Calendar and Age
Elapsed calendar time and chronological age.
Date Difference Calculator
Days between two dates
Age Calculator
Calendar age and age difference
Business Days
Weekday and federal-holiday-aware business day math.
Business Days Calculator
Working days with holiday options
Duration Math
Average durations and time add/subtract arithmetic.
Average Time Calculator
Average of multiple time durations
Time Add and Subtract Calculator
Add and subtract time durations
Results are calendar calculations for planning purposes only. Business-day and holiday schedules may change — verify critical deadlines with official sources.