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CalcWolf Auto Comparador de Tamanhos de Pneu
Auto

Tire Size Calculator

Compare tire sizes. Calculate diameter, circumference, and speedometer difference. Free tire calculator.

📅 Updated April 2026 Formula verified 📖 4 min read 🆓 Free · No sign-up

Regra dos 3%

O diâmetro total deve ficar ±3% do original. Pneus maiores: velocímetro marca menos que a real. Menores: marca mais. Diferença de 3% = erro de 2 km/h a 100. No Brasil, o CONTRAN exige conformidade — pneus fora da especificação podem reprovar na vistoria.

Plus-Sizing

Ao aumentar aro, diminua o perfil. 195/65R15 → 225/45R17: diâmetro muda ~1% (aceitável). Mais largo = melhor aderência mas mais consumo.

⚡ CalcWolf Insight

Consumer Reports found that at 4/32 inch tread remaining (halfway worn), wet braking distance increases 30%. At 2/32 inch (legal minimum), stopping distance nearly doubles vs new tires.

Frequently asked questions
Posso mudar de tamanho?
Sim, dentro de ±3% de diâmetro total. Acima: velocímetro errado, ABS perturbado.
Quando trocar?
1,6 mm de sulco (mínimo CONTRAN). Na prática: a 3 mm para segurança na chuva.
✓ Math logic verified against primary sources → See our verification process
Kevin Glover
Founder, CalcWolf · GLVTS · Blickr
All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →
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Found a bug or outdated data? Reports go directly to Kevin and are reviewed personally.