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Best of 2026

Best Free Date Calculators for 2026

Date calculations are deceptively tricky — months have different lengths, leap years add complexity, and business days skip weekends and holidays. Here are the best date calculators that handle all of this automatically.

Our Top Picks

  1. 1
    📆

    Days Between Dates

    Calculate exact days, weeks, and months between any two dates. Shows business days too.

    Try it free →
  2. 2
    💼

    Business Days Calculator

    Count business days excluding weekends and holidays. Supports US, UK, Canada, and Australia holidays.

    Try it free →
  3. 3
    📅

    Date Calculator

    Add or subtract days, weeks, months, and years from any date.

    Try it free →
  4. 4

    Countdown Calculator

    Live countdown to any event with days, hours, minutes, and seconds.

    Try it free →
  5. 5
    🎂

    Age Calculator

    Calculate exact age in years, months, and days. See days until next birthday.

    Try it free →

Pro Tips

  • A standard year has 365 days; a leap year has 366 (next leap year: 2028)
  • Most months have 4 weeks + 2-3 extra days, so "one month" is not exactly 4 weeks
  • Business days vary by country — always specify which holidays to exclude

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