Terms

Last updated October 8, 2026

These terms cover your use of Brocot at brocot.vercel.app, a free page published by PaintedApp, LLC of Portland, Oregon. Using the page means you accept them. They are short because the page asks nothing of you: no account, no payment, no data.

What Brocot is for

Brocot finds gear trains whose ratio comes close to a target, by Achille Brocot's method of 1861, and says how far off each one is. It is for clockmakers, model engineers, teachers and anyone curious about why the method works. You may use it, link to it, take screenshots of it and show it in a class or a talk.

What it is not for

Brocot works on the ratio alone. It does not check tooth form, module, centre distance, strength, wear or friction, and a train that is right on paper can still fail in metal. Check any train with your own drawings and your own calculations before you cut it, and never rely on the page for anything where a failure could hurt someone.

How exact it is

The page shows its own receipts: its figures beside the published worked examples it was checked against, and a list of what it does not do. The search is exhaustive inside the limits you set, and the arithmetic is done in whole numbers. Within those limits it is as exact as the test suite says, and no more.

Our work and others'

The page, its code and its drawings are © 2026 PaintedApp, LLC; the source code is licensed under the MIT licence. Published values are quoted from the sources named on the page, including Wikipedia and the OEIS under CC BY-SA 4.0, and every source is credited by name.

No warranty

Brocot is provided as it is, without any warranty, express or implied, including fitness for a particular purpose. It may change or go offline without notice.

Liability

To the fullest extent the law allows, PaintedApp, LLC is not liable for any loss arising from your use of Brocot, including the cost of wheels cut from a train it found. The page is free, so our total liability for any claim about it is limited to what you paid to use it, which is nothing. Some places do not allow these limits, and there they apply only as far as the law permits.

Changes and contact

If these terms change, the date at the top changes with them. Questions go to PaintedApp, LLC, 1327 SE Tacoma St #394, Portland, OR 97202, support@painted.app.