Cold weather tire pressure calculator
How much air did your tires lose in the cold? Tires lose about 1 PSI for every 10°F drop. Enter your numbers to see where yours are now.
An estimate based on how air pressure changes with temperature (about 1 PSI per 10°F). Tires also lose about 1 PSI a month on their own, so check with a gauge.
What to do when it gets cold
- Fill to the door sticker number, measured cold: before driving, or after the car has sat a few hours. That number is meant for cold tires, so don't add extra.
- Check again after a big cold snap. A 40°F drop can take 4 PSI out of every tire.
- Don't let air out on warm afternoons. Pressure rises as tires warm up; that's normal.
- Many tire shops check tire pressure for free: turn on the Pressure check filter on the free air map.
Why it happens, and why the warning light comes on in the morning: Why does tire pressure drop in cold weather? Want it on paper? Print our tire check card.
Questions
How much does tire pressure drop in cold weather?
About 1 PSI for every 10°F the temperature drops. A tire filled to 35 PSI on a 70°F afternoon reads about 31 PSI on a 30°F morning.
Should I add air when it gets cold?
Yes. Fill to the number on the sticker inside the driver's door, measured when the tires are cold (before driving, or after sitting a few hours). That number is meant for cold tires, so don't add extra to make up for the weather.
Why does the tire pressure light come on when it is cold?
The warning light comes on when a tire is about 25% below the recommended pressure. A cold night can push a tire that was already a little low past that point. It often goes off after driving warms the tires, but the tire is still low: add air.
Is this calculator exact?
It's an estimate based on how air pressure changes with temperature. Real tires also lose about 1 PSI a month on their own, and sun or driving warms them. Check with a gauge to be sure.