For the complete documentation index, see llms.txt.
15 endpoints

Time-Date API

Same bearer token, same credit pool, same JSON envelope as every other endpoint — drop them into apps, sites, workflows, or agents without rebuilding formulas, validation, or docs.

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Calendar
When Is Leap Yearwhen-is-leap-year
Check leap-year status and nearby leap years using Gregorian rules.
1cr · v2026-04-22
Date Tools
Add Business Days to Dateadd-business-days-to-date
Add or subtract business days from a date, skipping weekends under a configurable workweek pattern.
1cr · v2026-04-22
Age Calculatorage-calculator
Exact age in years/months/days plus total days, next-birthday countdown, day born, and zodiac sign.
1cr · v2026-04-22
Date Calculatordate-calculator
Add or subtract years, months, weeks, and days from a date.
1cr · v2026-04-22
Date Difference Calculatordate-difference-calculator
Calculate days, weeks, approximate months/years, and business days between two dates.
1cr · v2026-04-22
Days in Monthdays-in-month
Number of days in a given month/year with leap-year detection and calendar boundary details.
1cr · v2026-04-22
Time Between Two Datestime-between-two-dates
Calculate exact elapsed time between two ISO datetimes.
1cr · v2026-04-22
Week Number Calculatorweek-number-calculator
ISO 8601 and North American week numbers for a date, with week ranges, or the dates of a given ISO week.
1cr · v2026-04-22
Season
Winter Solstice Daywinter-solstice-day
Return winter solstice date/time for Northern or Southern Hemisphere, 2024-2030.
1cr · v2026-04-22
Time Calculators
Time Duration Calculatortime-duration-calculator
Calculate elapsed time between two times or datetimes.
1cr · v2026-04-22
Time to Decimal Convertertime-to-decimal-converter
Convert between hours/minutes/seconds and decimal hours.
1cr · v2026-04-22
Work Hours Calculatorwork-hours-calculator
Calculate weekly work hours, overtime, and optional pay from day entries.
1cr · v2026-04-22
Time Conversion
Military Time Convertermilitary-time-converter
Convert between 12-hour, 24-hour, and military time, including the spoken military form.
1cr · v2026-04-22
Time Zone Convertertime-zone-converter
Convert a local date/time between IANA time zones with DST-aware offsets, to one or more targets.
1cr · v2026-04-22
Unix Time Converterunix-time-converter
Convert between Unix timestamps and UTC ISO datetimes.
1cr · v2026-04-22