Landlord Calculator Suite

Eight free calculators for rental property owners. No signup, no data stored — every calculation runs in your browser. Built for the long-tail questions big calculator sites don't answer well.

1. Rental Cash Flow & Cash-on-Cash Return Calculator

Cash flow is what's left each month after every cost of owning the property — including two costs landlords often forget: a vacancy allowance (rent you won't collect while the unit sits empty or a tenant pays late) and a CapEx reserve (money set aside monthly for big, infrequent repairs like a roof or HVAC). Cash-on-cash return compares your annual cash flow to the actual cash you put into the deal (down payment, closing costs, and upfront repairs), which is a more honest measure than return on the property's full price.

Monthly cash flow = Rent − vacancy loss − CapEx reserve − management − tax − insurance − maintenance − other expenses − mortgage payment  |  Cash-on-cash = (Annual cash flow ÷ Total cash invested) × 100

Monthly cash flow
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Annual cash flow
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Cash-on-cash return
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Total monthly costs
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Educational only — not financial, tax, or legal advice. Vacancy and CapEx percentages are planning allowances, not predictions.

2. Rent Increase Calculator

Enter your current rent and either a percentage increase or a target rent, and this calculator annualises the result — because a modest monthly increase compounds into a meaningful annual difference, and it's easier to judge an increase against a full year of income. If you fill in both, the target rent is used.

New rent = Current rent × (1 + increase % ÷ 100), or the target rent you enter  |  Annual impact = Monthly change × 12

Notice rules vary: how much notice you must give, whether increases are capped, and what form the notice must take all depend on your state, city, and lease. This calculator does only the maths — check your local rules and your lease before sending any increase notice.

New monthly rent
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Monthly increase
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New annual rent
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Extra per year
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Educational only — not financial, tax, or legal advice.

3. Vacancy Loss Calculator

Every empty day costs you a day's rent. This calculator converts vacancy — entered as weeks plus extra days per year, covering turnover gaps, cleaning, repairs, and re-letting time — into an annual dollar loss and an effective vacancy rate, so you can budget for it instead of being surprised by it.

Daily rent = (Monthly rent × 12) ÷ 365  |  Annual vacancy loss = Daily rent × vacant days per year

Annual vacancy loss
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Vacancy rate
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Effective annual rent
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Cost per vacant day
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Educational only — not financial, tax, or legal advice.

4. Late Fee Calculator

Late fee structures are set by your lease — commonly a flat fee, a percentage of rent charged per day late, or both. Enter the terms from your lease and the number of days late, and this calculator totals the fee and the full amount due. It does not apply any legal cap: what fees are permitted, and any limits on them, depend on your jurisdiction and lease, so verify your terms are enforceable before charging them.

Late fee = Flat fee + (Rent × % per day ÷ 100 × days late)  |  Total due = Rent + Late fee

Late fee
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Total due (rent + fee)
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Educational only — not financial, tax, or legal advice. You supply the lease terms; this tool does not state what any law permits.

5. Security Deposit Deduction & Refund Tracker

When a tenancy ends, the amount you must return is the deposit minus lawful, documented deductions — unpaid rent, cleaning, repairs beyond normal wear and tear, and other charges your lease allows. Itemise the deductions below to get the refund amount and, if deductions exceed the deposit, the balance the tenant still owes. Keep receipts and photos for every line: documentation is what makes a deduction defensible. Deadlines for returning deposits and itemisations vary by jurisdiction — check yours.

Amount to return = Deposit − (unpaid rent + cleaning + repairs + other deductions)

Total deductions
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Amount to return
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Balance owed by tenant
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Educational only — not financial, tax, or legal advice.

6. Tenant Income Screener (3x Rent Rule)

A common screening benchmark is that an applicant's gross income should be at least three times the monthly rent — the idea being that rent then takes no more than about a third of income, leaving room for other obligations. Enter the rent and the applicant's gross monthly income to see the ratio, whether it meets the 3x benchmark, and the shortfall if it doesn't. Apply any screening criteria consistently to all applicants, and check local rules on what criteria are permitted.

Income ratio = Gross monthly income ÷ Monthly rent  |  Required income (3x) = Rent × 3

Income ratio
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3x rule
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Income needed for 3x
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Monthly shortfall
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Educational only — not financial, tax, or legal advice. The 3x rule is a common benchmark, not a legal standard or a guarantee of payment.

7. HELOC vs Cash-Out Refinance Comparison (Rental Property)

Both products turn rental equity into cash, but differently: a HELOC is a separate revolving line on top of your existing mortgage (often interest-only during the draw period, usually at a variable rate), while a cash-out refinance replaces your mortgage entirely with one new loan at a fixed or adjustable rate. Compare the same borrowed amount below. For the HELOC you'll see both the interest-only payment and the fully amortising payment, because which one applies changes the maths completely. Rates on investment properties, and whether a lender will offer either product on a rental at all, vary — get real quotes before deciding.

Amortising payment = P × (r ÷ 12) ÷ (1 − (1 + r ÷ 12)−months)  |  Interest-only payment = P × r ÷ 12  |  Total interest = (Payment × months) − Principal

HELOC — interest-only payment
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HELOC — amortising payment
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HELOC — total interest (amortising)
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Cash-out — monthly payment
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Cash-out — total interest
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Interest difference (HELOC − refi)
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Educational only — not financial, tax, or legal advice. This comparison excludes closing costs, fees, and rate changes on variable-rate products, all of which can change the answer.

8. Cap Rate Calculator (and Reverse: Implied Value)

Capitalisation rate measures a property's unlevered return: net operating income (NOI) divided by price. NOI is gross rental income minus operating expenses (tax, insurance, maintenance, management, vacancy) — but before mortgage payments, because cap rate is meant to compare properties independent of how they're financed. The reverse calculation answers the opposite question: at the cap rate you require, what price does a property's NOI justify?

NOI = Gross annual income − Annual operating expenses  |  Cap rate = (NOI ÷ Purchase price) × 100  |  Implied value = NOI ÷ (Target cap rate ÷ 100)

NOI
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Cap rate
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Implied value at target cap
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Educational only — not financial, tax, or legal advice.

Go deeper: the Premium Spreadsheet Pack Coming soon

Every calculator on this page, plus a full per-property tracker: monthly cash-flow log, CapEx planning, deposit and deduction records, and year-end tax-summary tabs — in one spreadsheet you own outright.

$29–$49  one-time. No subscription.

Launching soon — check back here for the release. No signup form, no email harvesting: when it's live, this section will link straight to the checkout.