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Tire Size Calculator
Compare tire sizes. Calculate diameter, circumference, and speedometer difference. Free tire calculator.
In this article
3% Rule
Overall diameter ±3% from original। Larger: speedo shows less than actual। Smaller: opposite। Check car manual for allowed sizes。 MRF, CEAT, Apollo, Bridgestone: top Indian brands。
Plus-Sizing
Bigger rim + thinner tyre: sportier look. 185/65R15 → 205/55R16: ~1% change (OK)。
⚡ 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
Can I change?▾
±3% diameter OK. Beyond: alignment + speedo issues。
When replace?▾
1.6mm legal min। 3mm recommended for monsoon safety。
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