Tyre load index — calculator and chart
The two- or three-digit number before the speed letter: what it means, what it carries. Look up an index, or enter the kg or lbs a tyre must carry and get the minimum index.
Open the toolFree toolkit
Tyre reference tools. Free. No signup.
The tables every tyre bay keeps pinned to the wall — load index, speed ratings, pressure conversions — as working calculators. Industry-standard ISO data, usable on any phone, right in the yard.
Tyre speed rating — symbol table
Every symbol from A1 to (Y): the rated maximum in km/h and mph, plus a reverse lookup — enter your road speed, get the lowest letter that's still legal.
Open the toolPressure converter — kPa, bar, psi, kg/cm²
Placard says kPa, compressor reads bar, imported gauge shows psi. Convert between all four instantly, with the quick-reference table underneath.
Open the toolWorkshop unit converter
Millimetres to inches, kilograms to pounds, km/h to mph and back — the everyday conversions for spec sheets written somewhere else.
Open the toolReading a sidewall?
Every number and letter on a tyre means something — how to read tyre sidewall markings walks through the size string, the load and speed ratings, the DOT date code and the rest of the alphabet soup. The knowledge base holds the deeper manufacturer databooks and standards.