Partial billing period
Select the complete billing period and the inclusive occupied dates. The calculator uses the actual number of calendar days and returns one exact rounded amount.
Date-only calculation
Select the complete billing period and the inclusive dates occupied within it.
Actual calendar days
No fixed 30-day assumption and no local-time or daylight-saving calculation.
$3,100.00 ÷ 31 days × 22 occupied days = $2,200.00
The selected billing period runs from 2026-07-01 through 2026-07-31 and contains 31 calendar days. Occupancy runs from 2026-07-10 through 2026-07-31, including both dates, for 22 days. Using actual calendar days, the rounded prorated amount is $2,200.00. This formula does not decide what a lease or local rule requires.
Learn how this calculation works
If July 1 through July 31 is the selected period, the denominator is 31. Occupying July 10 through July 31 counts 22 days because both endpoints are included. For $3,100, the calculation is $3,100 ÷ 31 × 22 = $2,200.
The denominator comes from the complete period you enter, not from the occupied dates. For a normal calendar-month agreement, enter the first and last calendar date of that month. If the relevant billing cycle runs from the fifteenth of one month through the fourteenth of the next, enter that complete cross-month period instead. The calculator then counts its actual inclusive days.
This distinction prevents a circular calculation. The occupied range identifies the numerator: the days for which you want the prorated share. The billing range identifies the denominator: all days represented by the entered rent. Both ranges must be explicit before a daily proportion can be reproduced.
Keep the billing start and end unchanged, then set occupied start to the move-in date and occupied end to the billing-period end. Because the endpoints are inclusive, moving in on the last day of a 31-day period produces one occupied day, not zero days.
Keep the same complete billing period, set occupied start to the period start, and set occupied end to the final included occupancy date. The calculator does not decide whether a key-return date, notice date, possession date, or another event controls; enter the dates required by the relevant agreement.
For February 1 through February 28 and $2,800 rent, the daily proportion is $2,800 divided by 28. Occupancy from February 15 through February 28 includes 14 days, so the prorated amount is $1,400. The period and occupied ranges each include both endpoints.
February 2028 contains 29 days. With $2,900 rent, each calendar day represents one twenty-ninth of the period. Occupancy from February 15 through February 29 includes 15 days, producing $1,500. The extra leap day changes both the denominator and, when occupied, the numerator.
Suppose the billing period is December 15 through January 14, a 31-day inclusive period, with $3,100 rent. Occupancy from January 1 through January 14 includes 14 days. The formula allocates 14 of 31 rent shares and returns $1,400 after exact-cent reconciliation.
These examples use round amounts so the arithmetic is easy to inspect. When the division produces fractions of a cent, the final amount is rounded once through the integer-cent allocator rather than rounding a displayed daily rate and multiplying that shortened number.
Rent can be prorated under several conventions. An actual-days method divides by the real number of days in the entered billing period. A fixed 30-day convention uses 30 as the denominator even in shorter or longer months. Some agreements use an annual daily rate or another written rule. These methods can return different amounts for the same move-in date.
This page implements only the actual-days method displayed in the formula. It does not automatically choose among conventions or infer the rule from a monthly rent amount. If a lease, landlord calculation, local requirement, or household agreement names another convention, use that source as the authority and treat this result only as a comparison.
When comparing two results, write down the denominator, whether dates are inclusive, the complete billing range, and the final rounding rule. A disagreement that looks like arithmetic may actually come from using different conventions or counting one endpoint differently.
After checking those assumptions, copy or record the rent amount, the two date ranges, the day counts, and the final prorated amount. That provides enough information for another person to reproduce the calculation without relying on a hidden daily-rate shortcut.
The final amount uses the same deterministic integer-cent allocation authority as the other RentSplit formulas. A whole-period occupancy always returns the complete selected rent. A one-day occupancy remains one share out of the actual period-day count, with the final result rounded once to whole cents.
This route applies one explicit actual-calendar-day formula. It does not select a legal convention, infer rent from a monthly lease, exclude weekends, build a payment schedule, or decide when possession began or ended.
Confirm the billing period, occupancy dates, and required convention with the relevant agreement before relying on the result.
No. It counts the actual calendar days between the selected billing-period start and end, including both dates.
Yes. Occupied start and occupied end are inclusive. A single occupied date counts as one day.
Yes. The selected start and end can cross month or year boundaries. The calculation uses date-only calendar arithmetic and handles leap days.
The daily rate is an explanatory division of total rent by billing-period days. The final prorated amount is allocated and rounded once to whole cents so it remains exact and reproducible.
No. It reports the selected actual-days formula. A lease, local rule, or agreement may specify another convention.