Calendar Calculator — Add or Subtract Time from a Date
Add or subtract days, weeks, months, and years from any date. Find future dates, deadlines, anniversaries, and day of the week for 2026.
Result Date
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2026 Key Dates
New Year's DayJan 1 (Thu)
Valentine's DayFeb 14 (Sat)
Easter SundayApr 5, 2026
Mother's DayMay 10 (Sun)
Memorial DayMay 25 (Mon)
Father's DayJun 21 (Sun)
Independence DayJul 4 (Sat)
Labor DaySep 7 (Mon)
HalloweenOct 31 (Sat)
ThanksgivingNov 26 (Thu)
ChristmasDec 25 (Fri)
New Year's EveDec 31 (Thu)
Frequently Asked Questions
- Adding months is trickier than adding days because months have different lengths. Always add months first, then adjust for month-end overflow. Example: January 31 + 1 month = February 28 (not March 3). Most programming languages handle this automatically. Our calculator handles edge cases correctly.
- Use the Doomsday algorithm or look up an online calendar calculator. For quick mental math: find the day of a known anchor date, then add/subtract days mod 7. Our calendar calculator shows the day of the week for any calculated result date automatically.
- Christmas 2026 falls on Friday, December 25, 2026. As of May 1, 2026, that's 238 days away. Christmas always falls on December 25, but the day of the week changes each year. In 2026 it's a Friday, meaning Christmas Eve (Dec 24) is a Thursday.
- 2026 US Federal Holidays: New Year's Day (Jan 1, Thu), MLK Day (Jan 19), Presidents' Day (Feb 16), Memorial Day (May 25), Juneteenth (Jun 19, Fri), Independence Day (Jul 4, Sat — observed Jul 3), Labor Day (Sep 7), Columbus Day (Oct 12), Veterans Day (Nov 11, Wed), Thanksgiving (Nov 26), Christmas Day (Dec 25, Fri).
- Add 90 days to today's date. If today is May 1, 2026 → 90 days later = July 30, 2026. Use our calendar calculator for any number of days, weeks, months, or years. For legal or financial deadlines, confirm whether you need calendar days or business days.
- Q1 ends March 31 (Tue) · Q2 ends June 30 (Tue) · Q3 ends September 30 (Wed) · Q4 ends December 31 (Thu). For fiscal years different from the calendar year, adjust accordingly. Tax deadlines often follow quarter-end dates with additional grace periods.
- Count only Monday–Friday, skipping weekends and holidays. Our calculator has a 'business days only' option. Manual method: divide the business days needed by 5 to get full weeks, add the remainder day by day from the next weekday. Example: 10 business days from Monday = 2 calendar weeks = exactly 14 days later.
- To find a future birthday or anniversary: enter the birth/start date, then add the number of years you want to project. Or enter today and a past date and subtract — the result shows how many days until the next occurrence. Many contracts use anniversary dates for renewals and penalties.