Rent Increase Calculator

How the calculator works

Start with the rent you pay now and the rent the landlord is asking for. The calculator subtracts one from the other, divides the difference by your current rent, and reports the increase in dollars and in percent. It then adds three things a percentage alone hides: the extra cost over a year, your new rent as a share of income, and a check against the rent limits in California and Oregon.

The core arithmetic is short enough to check on paper:

• Monthly increase = new rent minus current rent
• Percent increase = monthly increase divided by current rent, times 100
• Yearly cost = monthly increase times 12
• Rent share = new rent divided by gross monthly income, times 100

Gross income means pay before taxes and deductions. Housing agencies use that number, so it is the one that makes your result comparable to public data. Take-home pay is smaller, which means the same rent eats a larger share of the money that reaches your bank account.

The projection at the bottom of the results is the part most people skip. Rent that goes up 10% a year does not go up 50% in five years. Each increase lands on a bigger base, so five years of 10% adds up to a 61% jump.

Worked example: $1,500 raised to $1,650

A landlord proposes $1,650 for an apartment that rents at $1,500 today. Here is the whole chain:

• Increase: $1,650 - $1,500 = $150 a month
• Percent: $150 ÷ $1,500 = 10.0%
• Yearly cost: $150 x 12 = $1,800
• Share of a $5,000 income: $1,650 ÷ $5,000 = 33.0%

Ten percent is a number worth remembering. In California it is the threshold that decides whether the landlord owes you 30 days of notice or 90. It is also close to the ceiling that several state caps allow, so a 10% notice is often the largest increase a landlord can send without breaking a rule.

The table below shows what common percentages do to a $1,500 rent. Read it as a quick check on any notice you receive.

A 5% increase sounds gentle and still costs $900 over the year. That is a month of groceries for many households, and it is the reason a notice should be read as an annual bill, not a monthly one.

Why the dollar amount and the percentage tell different stories

Landlords quote increases both ways, and the two can point in opposite directions. A $150 increase is 16.7% on a $900 studio and 6.0% on a $2,500 house. Same dollars, different severity.

Percent is the better measure of how hard the increase hits your budget, because it tracks the size of the rent you already carry. Dollars are the better measure of what you have to find each month, because that is the amount you have to move out of savings or cut from something else.

Notice that the yearly cost is the same $1,800 in every row. What changes is the legal picture. A 16.7% increase on a $900 rent crosses the 10% line in California, which means a 90 day notice and, for a covered unit, a cap that the increase probably breaks. The same $150 on a $2,500 rent is a 6.0% increase that may sit inside the cap with a 30 day notice. Run both numbers before you decide how to respond.

Rent increases and the 30% line

The Department of Housing and Urban Development counts a household as cost burdened when housing takes more than 30% of gross income, and severely cost burdened above 50%. HUD measures gross rent, which is the rent plus the utilities you pay yourself, so a $1,650 rent with $150 of utilities counts as $1,800 of housing cost.

On a $5,000 monthly income, $1,650 of rent is 33.0% before utilities and 36.0% once $150 of utilities is added. Both numbers land past the 30% line. That does not make the apartment unaffordable in any legal sense. It does mean housing is taking money that would otherwise cover savings, car repairs and medical bills.

HUD explains these thresholds and the gross rent definition in its guide to measuring housing affordability. The practical lesson for a rent increase is simple: an increase that looks small in dollars can push a household that was comfortable at 28% over the line, and the utilities you pay are part of that math.

State limits in 2026: California and Oregon

There is no federal cap on rent increases for private housing. The rules come from states and cities, and two statewide systems cover a large share of renters.

California. The Tenant Protection Act, AB 1482, limits most increases to 5% plus the change in the regional cost of living, and never more than 10% in a 12 month period. The allowed figure is reset every August 1 using the April CPI for the metro area. For increases that take effect from August 1, 2026 through July 31, 2027, the limit is 8.7% in the Los Angeles metro area, 8.8% in San Francisco and 8.1% in the Riverside and San Bernardino area. New construction is exempt for its first 15 years, and a single family home owned by a person rather than a corporation can be exempt in some cases.

Oregon. The statewide limit for 2026 is 9.5%, calculated as 7% plus the West region CPI, capped at 10%. Tenancies in manufactured dwelling parks and marinas with more than 30 spaces are limited to 6% under a 2025 change. Oregon also allows only one increase in any 12 month period.

The California figures come from the state's published CPI updates and are repeated by county and city housing offices, including the Los Angeles County guide to rent increases. Oregon publishes its number each September for the following calendar year; the 2026 figure is on the Oregon rent stabilization page. Both pages are worth opening before you answer a notice, because the number changes every year.

Notice: 30 days or 90 days

An increase is not effective until you have proper written notice. California sets the clearest rule in the country, and it turns on the 10% line. If the increase is 10% or less of the rent charged at any time in the past 12 months, the landlord must deliver notice at least 30 days before it takes effect. Above 10%, the notice period is 90 days. The rule is in California Civil Code section 827, and the state attorney general summarizes it in the tenant rights guide.

Two details catch people out. First, the notice must be in writing. A call, a text or a conversation in the hallway does not start the clock. Second, when notice is served by mail, California adds five days to the period for delivery.

Other states vary. Most require 30 days for a month to month tenancy, some require 60, and a few require the increase to line up with the end of a rental period. If you have a fixed term lease, the rent usually cannot change until the term ends unless the lease itself allows it. Check your lease first, then your state or city rule.

Keep the envelope and the notice. If the timing or the amount turns out to be wrong, the paper is the evidence, and it is much easier to raise the issue before the new rent is due than after you have paid it for three months.

What the same increase costs over five years

Most rent increases are not one time events. If the same percentage shows up every year, the total cost is larger than the first notice suggests. Start at $1,500 and raise it 10.0% each year:

Five years of rent at the higher path costs $120,881.04. Five years at the old $1,500 costs $90,000. The difference is $30,881.04, and the gap widens every year after that. The last column shows the extra rent for that year alone; across the five years the increases add up to $30,881.04.

That is the argument for treating a 10% notice as more than a monthly annoyance. It is the start of a curve. If your income rises 3% a year while rent rises 10%, the share of income going to housing climbs every year, and the 30% line moves from a warning to a permanent condition.

When moving costs less than the increase

Sometimes the cheapest response is to move. Sometimes it is the most expensive thing you could do. The comparison takes about ten minutes.

• Cost of staying. The yearly increase, plus any utilities or fees that rise with it. On the example above that is $1,800 in year one.
• Cost of moving. A local move typically runs $400 to $1,500 for a small apartment, plus a security deposit on the new place, application fees, and the truck or movers.
• Rent at the new place. In many markets the asking rent for a comparable unit is higher than the rent you pay now, because long term tenants usually sit below market. Compare the actual listings, not the average.
• The hidden costs. A longer commute, a new school for the kids, losing a parking spot, and the time spent packing all belong in the total.

If the increase is $150 a month and moving costs $2,000, staying wins for the first year. If the increase is $300 a month and a comparable unit two blocks away rents for $100 less than your new rent, moving pays for itself in under a year.

Before you sign anything, ask the landlord in writing whether there is room to negotiate. A tenant who has paid on time for three years and offers to sign a 12 month renewal is in a better position than one who threatens to leave. If the increase looks illegal, contact a local tenant organization or legal aid office. Most cities have one, and the advice is free.

This calculator gives you an estimate to plan with, not legal advice. Rent rules change every year and vary by city, so confirm the current number with the agency that publishes it before you rely on it.