UK · EU reference Tyre Pressure

225/45R17 · passenger car · PSI

225/45R17 PSI chart (35 psi planning figure)

Size
225/45R17
Class
passenger car
Planning PSI
35
Planning bar
2.41

psi

35

2.41 bar · 241 kPa · passenger car planning figure

225/45R17 · 35 psi · 2.41 bar · 241 kPa — estimates. Placard wins.

PSI is the garage-hose number. For 225/45R17 a typical passenger car planning figure is 35 psi cold — about 2.41 bar or 241 kPa. The default 17-inch sport / saloon size. These rows are estimates interpolated for the size, not OEM for a named VIN. Low-profile {sz} does not want a “softer” pressure to recover ride. Stay at or slightly above the car’s original placard if load index is kept.

Estimated 225/45R17 pressure by load

Plus-sizing to 225/45R17 from a taller OEM tyre usually keeps the same placard if the load index is equal or higher.

ConditionFront (est.)Rear (est.)
Driver only / unladen35 psi / 2.41 bar / 241 kPa35 psi / 2.41 bar / 241 kPa
Typical occupancy36 psi / 2.48 bar / 248 kPa37 psi / 2.55 bar / 255 kPa
Motorway + luggage (sketch)37 psi / 2.55 bar / 255 kPa38 psi / 2.62 bar / 262 kPa

PSI, bar and kPa

1 bar ≈ 14.5 psi; 1 psi ≈ 6.89 kPa. Planning midpoint for 225/45R17: 35 psi = 2.41 bar = 241 kPa.

PSIBarkPa
312.14214
322.21221
332.28228
342.34234
352.41241
362.48248
372.55255
382.62262
392.69269
402.76276
412.83283
422.90290
432.96296
443.03303
453.10310
463.17317
473.24324

What 225/45R17 means

A 225/45R17 on a passenger car is a geometry. Two cars can share the size and disagree on PSI because mass and axle split differ.

The default 17-inch sport / saloon size. Rim diameter 17 in; section 225 mm. Estimates on this page assume a typical load index for the passenger car class.

Placard versus sidewall

The sidewall of a 225/45R17 may say 51 psi or 350 kPa. That is a carcass maximum. Operating pressure is the tyre-information placard on the driver’s door pillar.

Cars often seen on 225/45R17

These catalogue models are often seen on 225/45R17 or a close OEM neighbour. Open the vehicle chart for axle-specific PSI and bar.

BMW 320Volkswagen GolfFord MondeoVolkswagen PassatHonda Civic

How to set 225/45R17

  1. Measure before the school run, not after the motorway.
  2. Write LF / RF / RR / RL. Do not keep 225/45R17 numbers in your head.
  3. Add air in short bursts toward the placard, using 35 psi only as a map.
  4. If one 225/45R17 is 4 psi down, hunt for a nail before you blame the weather.
  5. Log date, ambient temperature and the four readings.

Temperature drift

Roughly 1 psi per 5–6 °C. The table uses 35 psi as a 20 °C baseline for 225/45R17.

AmbientGaugeBarkPaNote
−5 °C (hard frost)32 psi2.21 bar221 kPaGauge reads low; do not overfill once warm
0 °C33 psi2.28 bar228 kPaGauge reads low; do not overfill once warm
8 °C (UK winter morning)34 psi2.34 bar234 kPaGauge reads low; do not overfill once warm
20 °C (set cold here)35 psi2.41 bar241 kPaBaseline for this size sketch
30 °C37 psi2.55 bar255 kPaDo not bleed a hot 225/45R17
38 °C (heatwave tarmac)38 psi2.62 bar262 kPaDo not bleed a hot 225/45R17

A cheap gauge and a monthly habit will do more for a set of 225/45R17 than nitrogen upsells.

Questions about 225/45R17

What is 225/45R17 in bar?

35 psi is 2.41 bar. Add a tenth of a bar if the placard’s laden column is higher, which is common on vans that wear this size.

Is 225/45R17 the same as a plus-size swap?

Only if that is the size you fitted. Overall diameter should stay close to OEM. Pressure still follows the car, with load index at or above original.

What is 225/45R17 in kPa?

241 kPa is the planning midpoint (100 kPa = 1 bar). 248 kPa is one PSI higher.

Should I bleed pressure after a motorway run?

No. Heat raises the gauge. Set cold only. Bleeding a hot tyre leaves it low the next morning.

What PSI should 225/45R17 tyres be?

A passenger car planning figure is about 35 psi cold (2.41 bar / 241 kPa). Confirm on the vehicle placard — two cars can share 225/45R17 and not share a sticker.

Handbook: placard · bar vs PSI · cold inflation · all sizes