How Many Weeks Are in a Year?
Explain full seven-day weeks, leftover days and how ISO week numbering differs.
Archives: Time Calculation Guides
Follow worked examples for adding time, converting units, calculating work hours, and working with dates.
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Time arithmetic
Conversions
Work hours
Spreadsheets
Calendars
Practical uses
What Happens When You Add a Month to a Date?
Explain month-end clamping, leap years and why adding a month differs from adding 30 days.
How to Add Video Runtimes and Create Chapter Timestamps
Build cumulative chapter offsets from clips and distinguish total runtime from timestamps.
How to Calculate Playback Time at Different Speeds
Find actual viewing or listening duration at a specified playback rate.
How to Estimate Speaking Time From a Word Count
Estimate a rehearsal time range using measured words per minute and pauses.