Prorated Rent Calculator
Three common methods side by side, with the formula for each.
Actual days in month
30-day month
Yearly daily rate
Which method applies is set by your lease and, in some places, by local rules. Check your lease before you pay or charge an amount. This is arithmetic, not legal advice.
How It Works
Enter the monthly rent, choose whether you are moving in or out, and pick the date. The calculator counts the days you occupy the place that month, then multiplies by three different daily rates. Results update as you type.
Moving in on day D of a month with N days: you pay for days D to N, which is N − D + 1 days when the move-in day counts. Moving out on day D: you pay for days 1 to D, which is D days when the move-out day counts. Untick the box to leave that day out (one day fewer).
If the days come to the whole month, there is nothing to prorate and every method gives the full rent. Amounts are rounded to the cent only at the end; the daily rate is not rounded first.
The Three Methods
| Method | Daily rate | Notes |
|---|---|---|
| Actual days | Rent ÷ days in that month | Divides by 28, 29, 30 or 31, so a day in February costs more than a day in March. |
| 30-day month | Rent ÷ 30 | Same daily rate every month, sometimes called a banker's month. |
| Yearly rate | Rent × 12 ÷ 365 | Same daily rate all year. This calculator uses 365 days even in a leap year. |
None of these is the “right” one. They are all in common use, and the gap between them is largest in February. The guide to why prorated rent calculators differ walks through a full example.
Things to Check in Your Lease
- Which daily rate it uses, if it names one.
- Whether the move-in and move-out days are charged.
- Whether the first partial month is due with the first full month.
- Whether the landlord rounds the daily rate to the cent before multiplying, which can shift the total by a few cents.
Frequently Asked Questions
How do I calculate prorated rent?
Work out a daily rate, then multiply it by the number of days you occupy the place that month. The three common daily rates are monthly rent divided by the days in that month, monthly rent divided by 30, and monthly rent times 12 divided by 365. This calculator shows all three so you can see which one your figure matches.
Is prorated rent based on 30 days or the actual days in the month?
It depends on the lease and, in some places, local rules. Some landlords divide by the actual days in the month (28 to 31), some use a flat 30-day month, and some use a yearly daily rate. Check your lease for the method it names.
Why do prorated rent calculators give different answers?
They use different daily rates. For 1,500 rent and a move-in on February 15 of a non-leap year (14 days), actual days gives 750.00, a 30-day month gives 700.00 and a yearly daily rate gives 690.41. Whether the move-in or move-out day itself is counted can add or remove one more day.
Is the move-in day counted in prorated rent?
Usually yes, because you have the keys that day, but it is a convention, not a law of arithmetic. This calculator counts the move-in day, and the move-out day, by default; untick the box to leave that day out. Check what your lease says.
How is February handled in a leap year?
The actual-days method divides by 29 in a leap year and 28 otherwise, so the same date gives a different amount. The 30-day method always divides by 30, and the yearly method here always uses 365 days. Some leases use 366 days in a leap year, which changes the yearly result by a few cents.
Are my numbers sent anywhere?
No. Every calculation runs in your browser as you type, so nothing you enter is uploaded or stored.