Prorated Rent Calculator

The full monthly rent from your lease, before proration.
Move-in or move-out?
The year matters: February has 29 days in a leap year.
Day of the month you move in or out.
Your lease names the method that counts. The result below compares all three, so you can see why a landlord's number may differ.
Standard practice counts that day. Uncheck it only if your lease says the day itself is excluded.
Deposits are NOT prorated. If entered, the full amount is added to the total due at signing.

Try it: $1,500 rent, move in on the 15th of a 30-day month = $800.00 (16 days at $50.00/day).

Quick Answer: how to calculate prorated rent

Prorated rent = (monthly rent ÷ days in the month) × days occupied.

That is the whole method. Divide your full monthly rent by the number of days in the move-in or move-out month to get the daily rent amount, then multiply by the number of days you actually occupy the property. Example: $1,500 rent, moving in on June 15 of a month with 30 days. Daily rate: $1,500 ÷ 30 = $50.00 per day. Days occupied: June 15 through June 30, counting the move-in day, is 16 days. Prorated rent: $50.00 × 16 = $800.00.

Two things change that number in practice, and they explain almost every disagreement with a landlord’s figure: which method your lease uses to compute the daily rate, and whether the move-in or move-out day itself is counted. The calculator above shows all three methods side by side for your exact dates, so you can see both effects in dollars before you pay or quote a figure. In short, the prorated rent amount comes down to the day the tenant moves in or out, the days in the month, and the method the lease names.

How to use this calculator

Enter your full monthly rent, choose move-in or move-out, then pick the month, year, and day. The year matters because February has 29 days in a leap year and 28 otherwise, which changes both the daily rate and the day count. Pick the calculation method your lease names for calculating the prorated rent — actual days in the month is the most common and is the default — and leave “Count the move-in / move-out day itself” checked unless your lease says that day is excluded. If you want the total cash needed at signing, add your security deposit; it is added in full, because deposits are never prorated.

The result shows your prorated rent, the daily rate, the days in the month, the days occupied, and the exact dates covered, plus the working with your own numbers. Below that, the comparison table shows what the other two methods would give for the same rent and dates, and how much each differs from your main result.

The formula, step by step

  1. Find the daily rate. Dividing the monthly rent by the days in the month gives it. For a 30-day month at $1,500, that is $50.00 per day. For a 31-day month at the same rent, it is $48.39 per day — the same rent buys a cheaper day in a longer month.
  2. Count the days occupied. That is the days the tenant will occupy the unit. For a move-in, count from the move-in day through the last day of the month, including the move-in day unless your lease says otherwise. For a move-out, count from the 1st through the move-out day.
  3. Multiply. Daily rate × days occupied = prorated rent. Round only the final total to the nearest cent; rounding the daily rate early is how small errors creep in.

Worked example: move-in

Rent is $1,500 per month. You move in on January 15, 2026. January has 31 days, and you occupy January 15 through January 31 — 17 days, counting the move-in day.

  • Daily rate: $1,500 ÷ 31 = $48.3871 per day
  • Prorated rent: $48.3871 × 17 = $822.58

If your lease instead used the flat 30-day method, the same dates would cost $50.00 × 17 = $850.00. If it used the 365-day method, it would be ($1,500 × 12) ÷ 365 = $49.3151 per day × 17 = $838.36. Same rent, same dates, three answers — a $27.42 spread between the highest and lowest. That is why the first question to ask a landlord is always which method they used.

Worked example: move-out

Rent is $1,800 per month. You move out on October 10, 2026. October has 31 days, and you pay October 1 through October 10 — 10 days.

  • Daily rate: $1,800 ÷ 31 = $58.0645 per day
  • Prorated rent: $58.0645 × 10 = $580.65

Note that move-out math is the same formula run in the other direction: the only difference from move-in is which days you count. If you move out on the last day of the month, you owe the full month — there is nothing left to prorate — and the calculator says so plainly.

Worked example: February and leap years

February is where proration surprises people, because the daily rate is higher in a short month. Rent is $2,000 per month and you move in on February 10.

  • February 2026 (28 days): you occupy February 10–28, 19 days. Daily rate $2,000 ÷ 28 = $71.4286. Prorated rent: $71.4286 × 19 = $1,357.14.
  • February 2024, a leap year (29 days): you occupy February 10–29, 20 days. Daily rate $2,000 ÷ 29 = $68.9655. Prorated rent: $68.9655 × 20 = $1,379.31.

The leap-year move-in costs more in total even though the daily rate is lower, because you occupy one extra day. If your calculator ignores the year, it gets February wrong — this one does not.

The three methods, compared

Actual days in the month (most common). Divide by the real number of days in that month: 28, 29, 30, or 31. This is the fairest method because it matches the calendar, and it is the default here.

Flat 30-day month. Divide by 30 no matter what month it is. Simpler bookkeeping, and common in commercial leases. Watch for two quirks: in February it charges a higher daily rate than the calendar justifies (dividing 28 days of rent by 30), and in a 31-day month it can produce more than one full month’s rent — for example, a January 1 move-in at $1,500 gives $1,550. The calculator flags that case rather than hiding it; check whether your lease caps prorated rent at the full monthly amount.

365-day year. Multiply monthly rent by 12 to get annual rent, divide by 365 to get a true daily rate, and multiply by days occupied. This gives the same daily rate every month of the year, so it usually lands slightly below the actual-days figure in 31-day months and slightly above it in February.

Your lease names the method that counts. If it is silent, the actual-days method is the safest default: it is what most landlords and small-claims courts expect, and it is the easiest to explain.

What the calculator does that most others do not

Most prorated rent calculators online do one method and stop. This one was built from the gaps in the top-ranking pages:

  • Move-in and move-out in one tool. Many calculators only handle move-ins; for move-ins or move-outs mid-month, the math is the same either way.
  • All three methods in one table, with dollar differences. You do not have to run the math three times to understand why your landlord’s number differs from yours.
  • A day-inclusion toggle. Whether the move-in or move-out day itself counts is the second most common cause of a mismatch, and most tools never let you change it.
  • Total due at signing. Add a security deposit and the calculator adds it in full — never prorated — so you see the actual check you will write.
  • February and leap years handled by the year picker. Picking 2024 vs. 2026 changes February automatically.
  • Honest edge cases. A day-1 move-in or last-day move-out is labeled a full month, and a 30-day-method result above full rent carries a warning instead of being quietly capped.

Common mistakes

1. Counting the wrong days. The classic error is forgetting the move-in day itself: June 15 in a 30-day month is 16 days occupied (15th through 30th), not 15. One day on a $1,500 lease is $50 — enough to argue about, so count together with your landlord.

2. Using the wrong month’s day count. Dividing by 30 when the month has 31 days (or 28) gives a different daily rate and a different answer. Always divide by the days in the month you are actually prorating.

3. Rounding the daily rate too early. $1,500 ÷ 31 is $48.3871, not $48.39, until the final step. Rounding early and then multiplying can shift the total by a few cents — small, but it is exactly the kind of discrepancy that makes a tenant distrust a landlord’s math. This calculator keeps the full daily rate until the final rounding.

4. Prorating the security deposit. Deposits are not prorated. You pay the full deposit stated in your lease no matter which day you move in. Only the rent itself is prorated. The same usually applies to non-refundable move-in fees.

5. Assuming proration is automatic. In most places, proration is standard practice but not legally required — a landlord can, in principle, charge the full month if the lease allows it. Ask before you sign — whether you deal with the landlord directly or a property management company — and get the answer in writing. If the lease names a method, that method governs even if another method would give you a lower number.

How to double-check a landlord’s figure

  1. Ask which method they used: actual days, flat 30-day, or 365-day.
  2. Count the days together, and confirm whether the move-in or move-out day itself is included.
  3. Run both versions in the comparison table — or divide the rent amount by the number of days in the month yourself — and see which one matches their number.
  4. Get the final rent payment figure in writing before you pay — a one-line email confirmation beats a verbal quote.
  5. For a move-out, check the notice rules in your lease first: some leases charge the full month if proper notice was not given, even if you leave early.

Frequently asked questions

1. What is prorated rent?
Prorated rent is the partial month’s rent you pay when you move in or out in the middle of a month instead of on the 1st. You pay only for the days you occupy the unit — that is the rent due for the partial month — calculated as (monthly rent ÷ days in the month) × days occupied.

2. How do I calculate prorated rent?
Divide your monthly rent by the number of days in the move-in or move-out month to get a daily rate, then multiply by the number of days you occupy the unit. Example: $1,500 ÷ 30 days = $50.00 per day; 16 days occupied = $800.00.

3. Do I pay rent for the day I move in?
Usually yes. Standard practice counts the move-in day itself, so a January 15 move-in is charged for January 15 through January 31 (17 days). Some leases exclude that day, which is why this calculator has a toggle for it. If your lease is silent, assume the day counts and confirm with your landlord in writing.

4. Is prorated rent calculated using 30 or 31 days?
It depends on the method your lease uses. The most common method divides by the actual days in the month (31 for January, 30 for April, 28 or 29 for February). The flat 30-day method always divides by 30, whatever the month. The two give different answers in every month except 30-day months — run both in the comparison table to see the difference for your dates.

5. How is prorated rent calculated when moving out?
The same formula, counting from the 1st through your move-out day. For example, $1,800 rent with an October 10 move-out in a 31-day month: $1,800 ÷ 31 = $58.06 per day × 10 days = $580.65. Check your lease’s notice requirements first, since some leases charge the full month without proper notice.

6. Is the security deposit prorated too?
No. A security deposit is almost never prorated — you pay the full deposit amount stated in your lease regardless of which day you move in. Only the rent itself is prorated. This calculator keeps deposits separate and adds them to your total due at signing without prorating them.

Disclaimer

This calculator is for general information only. It is not legal, financial, or tax advice, and it does not replace your lease agreement. Your lease names the proration method that applies to you, and local tenant law may add requirements in some places — check your lease first, then the tenant rules where the property is located, and confirm the final figure with your landlord in writing before paying. Results are rounded to the nearest cent; daily rates are shown to four decimal places and kept unrounded until the final step.

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