Add Days Calculator
The Add Days Calculator adds two periods measured in days into a single combined total. Use it to add up separate spans of time — for example the lengths of two trips, two project phases, or two billing cycles. Enter each period in days and you get the total instantly, plus the equivalent in weeks.
Formula
Total Days = First Period + Second Period
- Add the two day counts to get the combined total: Total = A + B.
- The result is also shown in weeks (total ÷ 7) for quick reference.
- Use whole numbers for calendar days, or decimals if you are tracking partial days.
- To add a number of days to a specific calendar date instead, use the Add Days to Date calculator.
Example Calculation
Inputs
- First period (days): 5
- Second period (days): 10
Add a 5-day period and a 10-day period: 5 + 10 = 15 days, which is about 2.14 weeks.
Frequently asked questions
What does this calculator do?
It adds two periods measured in days and returns the combined total, along with the equivalent number of weeks.
When should I use it?
Use it to total separate spans of days — such as combining the lengths of two holidays, two project phases, or two billing cycles.
Can I enter partial days?
Yes. You can enter decimals (for example 2.5) if you are tracking partial days.
How do I add days to a calendar date instead?
Use the Add Days to Date calculator, which takes a start date and adds (or subtracts) a number of days to find the resulting date.
How is the weeks figure calculated?
It divides the total number of days by 7.