Prorated Rent Calculator
Moving in or out partway through the month? Work out the exact rent you owe for the days you actually occupy the unit — this doubles as a daily rent calculator. Enter your monthly rent and days, pick the proration method your lease uses, and see the per-day rate and amount due instantly.
Prorated rent = daily rent × days occupied. For $1,500 rent in a 30-day month, occupying 21 days, the daily rate is $1,500 ÷ 30 = $50.00/day, so you owe $50 × 21 = $1,050.00. The days-in-the-month method is the most common and fairest, but your lease's stated method always governs.
Enter your numbers
New to this? Leave the defaults — they match the worked example below — and just change the rent and days. Results update as you type.
How to use it
- Enter your monthly rent — the full amount for a complete month (the default is $1,500).
- Count the days you'll occupy the unit this month and type that in. If you move in on the 10th of a 30-day month and stay through the 30th, that's 21 days (counting both the 10th and the 30th).
- Pick the proration method your lease uses. "Days in the actual month" is the most common; switch to a flat 30-day month or the 365-day method only if your lease says so.
- Set "Days in the month" to the length of your month (28, 29, 30 or 31) — this only matters for the days-in-month method.
- Read the result. The headline shows the prorated rent due; the tiles show the daily rate, days occupied, full rent and the method used.
How prorated rent works
"Prorating" rent simply means charging for a portion of the month instead of the whole thing. It comes up whenever you don't live in the unit for a full calendar month — most often when you move in partway through a month, but also when you move out mid-month or end a lease early. Rather than pay a full month's rent for days you weren't there, you pay a daily rate multiplied by the number of days you actually occupy the home.
The only thing that varies between landlords is how they work out that daily rate. There are three common approaches. The days-in-the-month method divides the rent by the number of days in that specific calendar month, so the daily rate is slightly higher in February and slightly lower in a 31-day month — it reflects the true value of each day in that month. The flat 30-day method always divides by 30, which keeps the daily rate constant year-round but means tenants slightly overpay in 31-day months and underpay in February. The 365-day method multiplies the rent by 12 and divides by 365, spreading the annual cost evenly across every day of the year.
None of these is universally "the law" in most areas, so the method that applies to you is whatever your lease specifies. If the lease is silent, ask your landlord which they use before you sign — the difference is usually small, but it's worth confirming in writing so the move-in payment isn't a surprise.
The formula & how we calculate it
Every method follows the same two-step shape: find the daily rent, then multiply by the days you occupy the unit. Only the daily-rent step changes.
Worked example (the defaults above): you move in on the 10th of a 30-day month and occupy the 10th through the 30th — that's 21 days (inclusive of both the move-in day and the last day) — at a monthly rent of $1,500.
- Days in the month: $1,500 ÷ 30 = $50.00/day → $50.00 × 21 = $1,050.00.
- Flat 30-day month: $1,500 ÷ 30 = $50.00/day → $50.00 × 21 = $1,050.00 (identical here, because this month already has 30 days).
- Days in the year (÷365): $1,500 × 12 ÷ 365 ≈ $49.32/day → $49.32 × 21 ≈ $1,035.62.
Notice the methods only diverge when the month isn't exactly 30 days, or when you use the 365-day approach. In a 31-day month, for instance, the days-in-month daily rate drops to $1,500 ÷ 31 ≈ $48.39, while the flat 30-day method still charges $50.00 — which is why the flat method slightly favours the landlord in longer months.
Counting your move-in days (inclusive)
The single most common mistake is counting the days wrong. Proration is normally inclusive: you count the move-in day itself, because you have the keys and access to the home from that date. So if you move in on the 10th of a 30-day month and the month ends on the 30th, you occupy the 10th, 11th, … 30th — which is 21 days, not 20. A quick way to get it right: subtract the move-in day number from the last day of the month, then add 1 (30 − 10 + 1 = 21).
When you're moving out mid-month, the same logic applies to the days at the start of the month up to and including your last day. A small number of landlords count the move-out day differently, so if you're ever unsure, ask which days they include and confirm the figure in writing.
Glossary
- Prorated rent
- Rent charged for only the part of a month you actually occupy the unit, instead of a full month's rent.
- Daily rent (daily rate)
- The monthly rent divided down to a per-day figure. How you divide it (by days in the month, by 30, or by 365 from the annual rent) depends on the proration method.
- Days occupied
- The number of days in the month you have access to and possession of the unit. Usually counted inclusively of the move-in day.
- Proration method
- The rule for converting monthly rent into a daily rate — days-in-the-month, flat 30-day, or 365-day. Set by your lease.
Frequently asked questions
How is prorated rent calculated?
Prorated rent is the daily rent multiplied by the number of days you occupy the unit. The most common method divides the monthly rent by the number of days in that calendar month to get the daily rate. For example, $1,500 rent in a 30-day month is $1,500 ÷ 30 = $50 per day; occupy 21 days and you owe $50 × 21 = $1,050. Some leases instead use a flat 30-day month or divide the annual rent by 365.
What does prorated rent mean?
Prorated rent means you pay only for the portion of the month you actually live in the unit, rather than a full month's rent. It comes up when you move in or move out partway through a month. Instead of paying the whole month, you pay a daily rate for just the days you occupy the home.
Which proration method is correct?
Whichever method your lease specifies governs — there's no single legal standard in most places. The days-in-the-month method (rent ÷ days in that calendar month) is the most common and is generally considered the fairest, because it charges the true daily value of that specific month. A flat 30-day month is simpler but slightly overcharges in 31-day months, while the 365-day method spreads the cost evenly across the year. If your lease is silent, ask your landlord which they use before you sign.
Do I count the move-in day?
Usually yes. The day you take possession is normally counted as a day you occupy the unit, because you have access from that date. Counting is typically inclusive: move in on the 10th of a 30-day month and stay through the 30th and that's 21 days (30 − 10 = 20, plus 1 for counting both ends). Confirm the exact convention with your landlord, since a few count the move-out day instead.
Is prorated rent always for moving in?
No. Proration applies any time you occupy a unit for part of a month — moving in mid-month, moving out mid-month, or ending a lease early. The math is identical: count the days you actually occupy the home and multiply by the daily rate. Only the days you count change.