📆 Date Calculator
Need the date 90 days from today, or 6 months before a deadline? Pick a start date, choose add or subtract, and enter the amount.
How the Date Calculator works
Years and months are applied first (if the day does not exist in the new month, it moves to that month's last day), then weeks and days are added as exact calendar days.
Step-by-step calculation
- 1Pick the start date.
- 2Choose add or subtract.
- 3Enter years, months, weeks and days.
- 4Read the resulting date and weekday.
Worked example
June 1, 2026 plus 90 days is Sunday, August 30, 2026.
Date Calculator examples
| Days | Resulting date |
|---|---|
| 45 | Sunday, February 15, 2026 |
| 68 | Tuesday, March 10, 2026 |
| 90 | Wednesday, April 1, 2026 |
| 113 | Friday, April 24, 2026 |
| 135 | Saturday, May 16, 2026 |
Fixed values: Start date: Jan 1, 2026. Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use a Date Calculator?
Find due dates, deadlines, warranty end dates or follow-up dates in seconds.
Important factors that can affect your results
- Month-end rule: Jan 31 + 1 month = Feb 28 or 29.
- Whether the start day counts as day 1.
- Holidays are not skipped.
Frequently asked questions
Does it count the start date?
No. Adding 1 day to June 1 gives June 2. Add 1 if your rule counts the first day.
How are business days handled?
This tool counts every calendar day. Use the Business Days Calculator to skip weekends.
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Last reviewed November 2026 · How we build and check our tools · Report a problem