RENEWAL RENT OPTIMIZER · RUNS IN YOUR BROWSER · NOTHING UPLOADED

Are you raising rent too little, or too much?

Paste or upload your past lease renewals: current rent, the rent you offered, and whether the tenant renewed. Tell it what a move-out costs you. The tool fits a renewal-chance curve (logistic regression) of how often tenants stay at each size of increase, finds the increase with the highest expected income over the next lease inside the range you have actually offered, shows what a point more or less would do, and back-tests whether the size of the increase explains who stayed at all. If your offers never varied, it says so instead of guessing.

Your rent roll never leaves this browser tab. Statistical estimate from data you supply, not advice, and it does not know your local rent rules. Not legal, tax, or financial advice.

Your past renewals

The unit you are pricing

Renewed can be 1/0, renewed/left, yes/no, stayed/moved out. Leave out tenants whose lease has not ended. Turnover cost is cleaning, painting, repairs beyond the deposit, advertising and leasing fees; lost rent is added from the vacant days. Rows are read in the order given (oldest first) so the back-test can score your most recent renewals. At least 25 offers with 6 renewals and 6 departures, at four or more different increases.

Upload or paste your renewals, then click Analyse.

How it is calculated

Model: P(renew) = 1 ÷ (1 + e^−(a + b × x)), where x is ln(offered rent ÷ current rent). Fitted by Newton-Raphson on the log-likelihood with a tiny ridge so perfectly separated data cannot push the slope to infinity; the 95% interval uses the inverse Hessian. Expected income over the lease: P(renew) × offered rent × months, plus (1 − P) × the value of a departure, which is the new tenant's rent for the months after the vacancy, less your turnover cost. The best increase is searched on a fine grid only between the lowest and highest increase in your data. The 80% ranges and the chance the best increase beats your usual one come from 300 seeded bootstrap resamples (stayers and leavers resampled separately), so a result is reproducible. Back-test: the first 75% of rows fit the model, the last 25% are scored by log-loss against simply assuming your overall renewal rate.

Not modelled: the local market, rent control and notice rules, how long the tenant has lived there, how you have treated them, repairs owed, the state of the unit, and what a longer or shorter lease is worth. Increases are not random, so this is correlation, not an experiment. Unverified: checked against simulated renewals with known curves in unit tests, not against a published dataset or a commercial tool.

Common questions

What is a lease renewal rate?

It is the share of tenants who sign a new lease when their lease ends. If 40 tenants get a renewal offer and 34 sign, your renewal rate is 85%. The useful question is how that rate changes with the size of the rent increase you offer, and this tool measures that from your own past renewals.

How much should I raise rent at renewal?

Raise it until the extra rent from tenants who stay is outweighed by the cost of the ones you lose. A tenant who leaves costs you vacancy, cleaning and repairs, and the re-leasing work. This tool fits how your renewal chance falls as the increase rises, prices a move-out from the vacancy days and turnover cost you enter, and finds the increase with the highest expected income over the next lease, searching only inside the increases you have actually offered.

How many past renewals do I need?

At least 25 renewal offers with a result, at least 6 tenants who renewed and 6 who left, and offers that vary: four or more distinct increase levels with a typical spread of about one point or more. If you always offer the same increase, nothing in your history can say what would happen at another, so the tool refuses instead of guessing. Pool every unit you have managed; more is better.

What does a tenant turning over really cost?

Lost rent while the unit sits empty, cleaning and repainting, repairs beyond the deposit, advertising and leasing fees, and sometimes a concession for the next tenant. Enter your own vacancy days and turnover bill. The result is very sensitive to them, which is why the tool shows the cost of one move-out as its own number.

Why might the result be wrong?

Rent increases are not random. If you raised rent most in hot buildings or on tenants who had been there for years, the curve mixes that with the size of the increase and can even slope the wrong way; the tool flags that. It cannot see the local market, how you treated the tenant, or rent control limits. Treat the answer as a hypothesis for a small, reversible change in your renewal offers, not a number to bet the portfolio on.

Does it know my local rent control or notice rules?

No. Many places cap annual increases or require specific notice. The tool does not know your jurisdiction and will happily suggest an increase that is illegal where you are. Check the rules that apply to your unit before sending any offer.

Is my rent roll uploaded anywhere?

No. The file is read and analysed in this browser tab. Nothing is sent to a server, there are no accounts or cookies, and the tool never stores your tenants' data. It works offline once the page has loaded.