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Prorated rent calculator.
Enter the monthly rent and move-in date. Returns the exact prorated rent for the partial first month using three standard methods: actual days-in-month, flat 30-day month, or 365-day year (banker's method).
Calculation method
How prorated rent works
Three methods, three slightly different answers.
- ·Days-in-month method: monthly rent / days in that actual month * days occupied. Most accurate; varies with 28-31 day months.
- ·30-day method: monthly rent / 30 * days occupied. Simpler and lease-friendly; can over- or under-charge by a small amount.
- ·365-day method: (monthly rent * 12) / 365 * days occupied. Banker's method; produces the smallest prorate amounts; preferred when the lease spans partial months at start and end.
No US state mandates a specific method. Whatever the lease specifies governs. If the lease is silent, the days-in-month method is the most commonly used default in small claims cases.
Honest limits
The calculator is informational. It does not account for partial-day proration, early-termination clauses, or rent-concession lease terms. For contested cases, consult a licensed attorney.