225/60R18 · SUV / crossover · kPa
225/60R18 tyre pressure in kPa
- Size
- 225/60R18
- Class
- SUV / crossover
- Planning PSI
- 34
- Planning bar
- 2.34
kPa
234
2.34 bar · 34 psi · 100 kPa = 1 bar
225/60R18 · 34 psi · 2.34 bar · 234 kPa — estimates. Placard wins.
If the gauge only speaks kPa, 234 kPa is the sketch for this SUV / crossover size. Fine-tune to the vehicle that actually wears 225/60R18. Under-inflation cooks the shoulders of a 225/60R18; over-inflation wears the centre rib and bangs every cat’s eye.
kPa, bar and PSI
1 bar ≈ 14.5 psi; 1 psi ≈ 6.89 kPa. Planning midpoint for 225/60R18: 34 psi = 2.34 bar = 234 kPa.
| kPa | Bar | PSI |
|---|---|---|
| 207 | 2.07 | 30 |
| 214 | 2.14 | 31 |
| 221 | 2.21 | 32 |
| 228 | 2.28 | 33 |
| 234 | 2.34 | 34 |
| 241 | 2.41 | 35 |
| 248 | 2.48 | 36 |
| 255 | 2.55 | 37 |
| 262 | 2.62 | 38 |
| 269 | 2.69 | 39 |
| 276 | 2.76 | 40 |
| 283 | 2.83 | 41 |
| 290 | 2.90 | 42 |
| 296 | 2.96 | 43 |
| 303 | 3.03 | 44 |
| 310 | 3.10 | 45 |
| 317 | 3.17 | 46 |
Estimated 225/60R18 pressure by load
Load moves the rear first on a SUV / crossover. If the factory placard already has a laden column, use that — not this sketch for 225/60R18.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only / unladen | 34 psi / 2.34 bar / 234 kPa | 35 psi / 2.41 bar / 241 kPa |
| Typical occupancy | 35 psi / 2.41 bar / 241 kPa | 37 psi / 2.55 bar / 255 kPa |
| Motorway + luggage (sketch) | 36 psi / 2.48 bar / 248 kPa | 38 psi / 2.62 bar / 262 kPa |
What 225/60R18 means
Read 225/60R18 as width / aspect R rim. Nothing in the size string is a pressure. Pressure lives on the car, not moulded as 205 or 55.
Crossover / SUV highway size. Rim diameter 18 in; section 225 mm. Estimates on this page assume a typical load index for the SUV / crossover class.
Placard versus sidewall
This website maps size searches such as “225/60R18 psi”. It does not replace the VIN label. If the two disagree, the label wins.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for 225/60R18.
| Ambient | Gauge | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 31 psi | 2.14 bar | 214 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 32 psi | 2.21 bar | 221 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 33 psi | 2.28 bar | 228 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 34 psi | 2.34 bar | 234 kPa | Baseline for this size sketch |
| 30 °C | 36 psi | 2.48 bar | 248 kPa | Do not bleed a hot 225/60R18 |
| 38 °C (heatwave tarmac) | 37 psi | 2.55 bar | 255 kPa | Do not bleed a hot 225/60R18 |
How to set 225/60R18
- Measure before the school run, not after the motorway.
- Write LF / RF / RR / RL. Do not keep 225/60R18 numbers in your head.
- Add air in short bursts toward the placard, using 34 psi only as a map.
- If one 225/60R18 is 4 psi down, hunt for a nail before you blame the weather.
- Log date, ambient temperature and the four readings.
Cars often seen on 225/60R18
225/60R18 is a valid metric size in this register even if it is not on the curated OEM shortlist. Treat the 34 psi / 2.34 bar figure as a class estimate and confirm on the vehicle that actually wears it.
If the door sticker and this 225/60R18 page disagree, the sticker wins.
Questions about 225/60R18
Is 225/60R18 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 PSI should 225/60R18 tyres be?
A SUV / crossover planning figure is about 34 psi cold (2.34 bar / 234 kPa). Confirm on the vehicle placard — two cars can share 225/60R18 and not share a sticker.
Can I run 225/60R18 at a lower pressure for comfort?
Not as a habit. A soft 225/60R18 cooks the shoulders and dulls steering. Keep load index and stay on the placard.
What is 225/60R18 in bar?
34 psi is 2.34 bar. Add a tenth of a bar if the placard’s laden column is higher, which is common on vans that wear this size.
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.
Handbook: placard · bar vs PSI · cold inflation · all sizes