About this site

Radif Partners publishes independent calculators on everyday money and legal questions. This site answers the question every tenant in Germany faces sooner or later, when signing a new lease or opening a rent increase letter: is this rent allowed?

What we set out to do better

Search for a German rent index today and you find your city's PDF, or a calculator whose first question is the local reference rent, which is exactly the figure you were looking for. Whether your municipality has a 15 or 20 per cent cap, and whether the rent brake was in force on the day you signed, you are left to find in a state ordinance.

So this site does not ask you for the reference rent where it may calculate it itself: in Berlin from the 2026 index, in Hamburg from the 2025 index, in Dortmund from the 2025/2026 index. For every municipality it applies the rent brake and the increase cap from its state's ordinance, with start and end dates. That makes it more precise than the first Google result, which asks you for the reference rent and leaves your municipality's rules open.

How we work

Scripts read the Berlin, Hamburg and Dortmund values from the official publications, and tests check them against the worked examples in the brochures. The rent-brake lists, 729 municipalities across the states that have an ordinance, come from the official gazettes, and each count was checked against the official text. Cities that reserve the rights to their index are respected: we take no figure from them and link their official tool instead. The method page has the details.

What we are not

We are not a tenants' association, a law firm or a collection service for overpaid rent. We take no share of any refund, refer no one and give no legal advice on individual cases. In a dispute, the local tenants' association (Mieterverein), public advice centres or a tenancy lawyer can help.

Funding

The calculators are free and store nothing. If advertising ever appears, it will never sit above a calculator.

Written for newcomers

Every page exists in German and English. The English pages are written for people who moved to Germany and want to understand their first German lease; German terms are explained where they first appear.

Report an error

Has a city published a new rent index or a state changed an ordinance? Write to contact@mietcheck-rechner.de. See also the editorial policy and the legal notice.

Legal status 2026, checked on 12 October 2026.