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Inflation time

How long does it take to inflate a 245/60R18 tire?

Quick answer

A 245/60R18 tire (about 29.6 inches tall) holds roughly 58 liters. Raising it from 30 to 35 psi takes about 1 min 25 s with a compact 12V or cordless inflator, and filling it from flat to 35 psi about 9 min 53 s, or 3 min 38 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 58 liter tire: top-ups take about 1 min 25 s.

How long for each inflator class?

Times for one 245/60R18 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 psi20 L1 min 25 s54 s31 s
Top up 25 to 35 psi40 L2 min 49 s1 min 48 s1 min 2 s
Low tire 15 to 35 psi79 L5 min 39 s3 min 36 s2 min 5 s
Flat 0 to 35 psi138 L9 min 53 s6 min 17 s3 min 38 s

What do the numbers in 245/60R18 mean?

245 is the section width in millimeters. 60 is the sidewall height as a percentage of the width, here 147mm. R18 means radial construction on a 18 inch rim. Together they give an overall diameter of about 29.6 inches and an internal volume of about 58 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 39 s with a compact unit.

Inflators and a gauge for 245/60R18 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 245/60R18 tire?

About 58 liters, estimated from the sidewall size: 245mm wide, a 60 percent sidewall (147mm) and a 18 inch rim. To add 5 psi you pump in about 20 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 245/60R18 tire?

Yes. A compact unit tops it up in about 1 min 25 s and fills it from flat in about 9 min 53 s, within the duty cycle of most compact inflators. Always inflate to the door-jamb placard, not the sidewall maximum.

How much does a 245/60R18 tire lose in cold weather?

Like every tire, about 1 psi per 10 F drop. A 245/60R18 set to 35 psi at 70 F reads about 30 psi at 20 F. Put back the 19 liters of air it is missing when you check it on a cold morning.

Updated 2026-09-24