How to read this result
In the default example, monthly increase is $150.00. Results describe this input scenario; they are not a recommendation.
Change one assumption at a time to see how it affects the scenario. Compare periods and cost definitions consistently. Negative results show a modeled shortfall; an unavailable ratio needs a valid denominator.
Formula and methodology
Subtract old monthly rent from new monthly rent. Divide the difference by old rent for percentage change. Multiply the monthly dollar change by 12 for the annualized difference.
Enter percentages as whole numbers: 5 means 5%. When used as a factor, the calculation divides a percentage by 100. Percentage outputs multiply the final ratio by 100. Calculations retain precision internally; displayed amounts and rates are rounded to two decimals.
Variables and input definitions
- Current monthly rent (USD/month)
- Current rent. Minimum: 0.
- New monthly rent (USD/month)
- Proposed new rent. Minimum: 0.
Worked example
This example uses the exact prefilled inputs above. Reset defaults to restore this scenario after making changes.
| Item | Default scenario |
|---|---|
| Current monthly rent | $2,000.00 |
| New monthly rent | $2,150.00 |
| Item | Default scenario |
|---|---|
| Monthly increase | $150.00 |
| Percentage increase | 7.50% |
| Annualized difference | $1,800.00 |
Assumptions and limitations
Pure arithmetic. It does not determine whether a rent increase is legally permitted in a specific jurisdiction.
Results describe this input scenario; they are not a recommendation.
The tool uses values you supply. It does not retrieve market prices, verify leases or inspect a property. Results exclude items outside the listed inputs. Review local requirements and the relevant contract when a payment, fee or allocation depends on them.
Common mistakes
Percentage change uses the old rent, not the new rent, as its denominator. This tool does not decide whether an increase is lawful or whether required notice was given.
Sources and method references
These references provide context for the method and terminology. They do not endorse this tool or validate your property assumptions.
- GovInfo / HUD — 24 CFR §880.608 — Security deposits (federal housing program example)Program-specific example referencing state/local deposit requirements; not a national interest-rate rule.
Frequently asked questions
Can this calculate a rent decrease?
Yes. Enter a new rent below the old rent. The dollar, percentage and annualized changes remain negative.
What if previous rent is zero?
The dollar change still exists, but the percentage change has a zero denominator and is shown as N/A.