Add or subtract a number of days from any date to find the resulting calendar date.
Try an example
Load a ready-made sample into this tool and run it. Every result you see is calculated live by the tool itself — nothing here is a pre-written answer.
Sample: from: 2026-01-01; days: 30; dir: add
How to Use
- Pick a start date.
- Enter how many days to add or subtract.
- Read the resulting date and its weekday.
What this add days to date calculator does
This add days to date calculator moves any calendar date forward or backward by a number of days you choose. Pick a start date, enter how many days to add or subtract, and it shows the resulting date together with its weekday. It suits deadlines, delivery estimates, follow-up appointments, and any plan described as a set number of days from a known starting date.
When calendar-day counting is the right approach
Use calendar days when the rule you are following counts every day on the calendar, such as a 30-day notice period or a 90-day warranty window. This tool moves straight along the calendar and includes Saturdays and Sundays in the count. If a deadline is measured in working days instead, that calls for a business-day count between two dates.
Good to know
The count uses whole calendar days, so daylight-saving changes do not shift the resulting date. The tool works with the date alone and never asks for a time of day, which keeps the answer the same no matter when during the day you run it.
Frequently asked questions
How do I find the date 45 days from today?
Enter today's date as the start date, type 45 in the days field, choose Add days, and run the tool. It shows the date 45 days later and its weekday.
Does this calculator skip weekends?
No. It counts calendar days, so Saturdays and Sundays are included like any other day. For a count that leaves weekends out, use the business days calculator instead.
Can I subtract days to find an earlier date?
Yes. Choose Subtract days and the tool moves back from the start date by the number you enter. This helps find dates set a number of days before an event.
How to use Add or Subtract Days Calculator
- Pick a start date.
- Enter how many days to add or subtract.
- Read the resulting date and its weekday.
Limitations
Calendar days are used, so daylight-saving changes do not shift the resulting date.