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Inflation time

How long does it take to inflate a 235/60R18 tire?

Quick answer

A 235/60R18 tire (about 29.1 inches tall) holds roughly 53 liters. Raising it from 30 to 35 psi takes about 1 min 17 s with a compact 12V or cordless inflator, and filling it from flat to 35 psi about 9 min 0 s, or 3 min 19 s with a heavy-duty compressor.

AstroAI Tire Inflator Portable Air Compressor, 12V DC/120V AC Dual Power

AstroAI Tire Inflator Portable Air Compressor, 12V DC/120V AC Dual Power

A compact inflator is enough for a 53 liter tire: top-ups take about 1 min 17 s.

How long for each inflator class?

Times for one 235/60R18 tire using delivered flow at tire pressure, which is roughly 40 to 50 percent of the rated figure on the box: about 14, 22 and 38 liters per minute for the three classes.

JobAir to pumpCompactFast cordlessHeavy-duty
Top up 30 to 35 psi18 L1 min 17 s49 s28 s
Top up 25 to 35 psi36 L2 min 34 s1 min 38 s57 s
Low tire 15 to 35 psi72 L5 min 9 s3 min 16 s1 min 54 s
Flat 0 to 35 psi126 L9 min 0 s5 min 44 s3 min 19 s

What do the numbers in 235/60R18 mean?

235 is the section width in millimeters. 60 is the sidewall height as a percentage of the width, here 141mm. R18 means radial construction on a 18 inch rim. Together they give an overall diameter of about 29.1 inches and an internal volume of about 53 liters, typical of cars and crossovers, where any decent portable inflator copes.

Check pressure cold, before driving. All four tires from 30 to 35 psi take about 5 min 9 s with a compact unit.

Inflators and a gauge for 235/60R18 tires

Prices change often.

Nearby tire sizes

Before you rely on this: Inflate to the door-jamb placard pressure, measured cold, and follow the inflator maker's duty cycle. Researched from published specifications and verified owner reviews, not hands-on testing. General information, not professional advice; check your vehicle manual and your local law.

Frequently asked questions

What is the air volume of a 235/60R18 tire?

About 53 liters, estimated from the sidewall size: 235mm wide, a 60 percent sidewall (141mm) and a 18 inch rim. To add 5 psi you pump in about 18 liters of free air, because each 14.7 psi of pressure equals one tire volume of outside air.

Can a small tire inflator fill a 235/60R18 tire?

Yes. A compact unit tops it up in about 1 min 17 s and fills it from flat in about 9 min 0 s, within the duty cycle of most compact inflators. Always inflate to the door-jamb placard, not the sidewall maximum.

How much does a 235/60R18 tire lose in cold weather?

Like every tire, about 1 psi per 10 F drop. A 235/60R18 set to 35 psi at 70 F reads about 30 psi at 20 F. Put back the 17 liters of air it is missing when you check it on a cold morning.

Updated 2026-09-24