Add Days to a Date Calculator
Finds the date a number of days after another date.
Result
- Resulting date
- 3 Jan 2027
- Day of the week
- Sunday
How to use the add days to a date calculator
- Enter the start date.
- Enter the days to add.
- The results update as you type, or press Calculate.
- Read the resulting date first, then the supporting figures below it.
Formula
Result = start + n days.
Worked example
For example, with these inputs:
- Start date: 5 Oct 2026
- Days to add: 90
the calculator returns:
- Resulting date: 3 Jan 2027
- Day of the week: Sunday
Background
When sharing dates internationally, write the month as a word to avoid confusion between day-month and month-day formats.
Age is calculated in completed years, months and days. Someone born on 29 February is usually treated as turning a year older on 28 February or 1 March in non-leap years, depending on the rule being applied.
Frequently asked questions
How does the add days to a date calculator work?
It applies this formula: Result = start + n days.
Does this count Singapore public holidays?
No. It counts calendar days or weekdays. Subtract any public holidays in the period yourself.