Fitment calculators that don't lie.

Free, accurate wheel, tire, and suspension fitment tools — built for JDM and Euro platforms by people who actually fit wheels for a living.

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Math that's tested

100% unit-test coverage on all calculator math. Every formula is open and verifiable.

Operator-verified data

Every platform sheet is reviewed by a human before publish. Stale data shows a banner.

No fluff

No SEO-spam paragraphs. Just specs, calcs, and known-good setups.