Moving in or out partway through a month means paying rent for only the days actually occupied, not the full monthly amount — a calculation landlords and tenants both need to get right to avoid over- or under-charging.
This calculator divides your monthly rent by the actual number of days in that specific month to find a precise daily rate, then multiplies by the number of days you'll actually occupy the unit for the prorated total owed.
Using the actual days in that specific month (28, 29, 30, or 31) rather than a flat assumption of 30 gives a more accurate daily rate, since dividing by the wrong day count can noticeably skew the prorated amount, especially in February or 31-day months.
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Frequently asked questions
Should I use 30 days as a standard, or the actual days in the month?
Using the actual number of days in that specific calendar month gives the most accurate daily rate; some leases specify a flat 30-day divisor regardless of the actual month, so check your lease terms.
Does this work the same way for move-out prorating?
Yes, the same calculation applies whether you're prorating a partial first month (move-in) or a partial final month (move-out) — just enter the number of days actually occupied in that month.