Calendar references and planning tools.
This section groups the parts of the site that are about the structure of the year itself: week numbering, ordinal days, leap years, working-day calculations, and chart-style references.
Calendar pages by task
Plan by week
- Week Number
Current ISO week number with yearly context and even-odd scheduling help.
- ISO vs US Weeks
See how week numbering changes between the main systems people confuse.
Plan by business day
- Working Days
Count business days between dates and understand holiday-aware schedules.
- Date Calculator
Add or subtract days and compare dates when the task is plain calendar math.
- Countdown
Track the time remaining until a date or event.
Use year and day references
- Day of the Year
Current ordinal day with year progress and practical context.
- Leap Year
See how leap years affect annual numbering and date calculations.
- Julian Date Calendar
Browse full-year day-number charts for lookup and print use.
What makes this a distinct silo
Calendar pages answer questions about how the year is divided and counted. That includes week boundaries, leap-year effects, business-day counts, and year-based lookup tables. Those are different jobs from machine-readable time encoding and different again from timezone conversion.
Keeping these pages together creates a cleaner internal-linking pattern. Week-number searches should reinforce working-days pages and year charts before they leak into unrelated timestamp tools.