Tire Pressure by Temp

Cold snap coming? Get a heads-up the night before, so the low-pressure light doesn't surprise you in the driveway. Estimates only — always confirm with a gauge.

Tire pressure falls as the air gets colder. Enter the pressure printed on your door placard once, along with the temperature it was set at, and this app estimates what your tires would read at today's temperature — and roughly how much air it would take to get back to the placard number.

No sensors. No Bluetooth. Nothing to buy or mount.

Every other tire pressure app expects you to install hardware in your valve stems. This one is just arithmetic done carefully, using the temperature outside your window.

WHAT IT DOES

• Estimates today's pressure from your placard setting and the current temperature • Shows the top-up estimate — how much to add to reach your target • Pulls the current temperature automatically from your local forecast • Warns you the night before a cold morning, so a hard freeze isn't a surprise • Temperature slider to explore "what if it drops to 10°F?" • Home Screen widget shows the morning estimate without opening the app

BUILT FOR EVERY VEHICLE YOU OWN

Add as many as you like: car, motorcycle, bicycle, camper van, or trailer. Front and rear axles can carry different targets, and each vehicle keeps its own unit — because placards are printed in psi in one country and bar or kPa in the next.

• bar, psi and kPa, switchable per vehicle • Separate front and rear targets • Your fleet stays on your device

THE MATH, IN THE OPEN

The estimate is the ideal gas law at constant volume. The step most rules of thumb skip is converting gauge pressure to absolute pressure before applying the ratio, then converting back. Skipping it overstates the change by roughly 40 percent. This app does the conversion, and the settings screen shows you the formula so you can check the work yourself.

PLEASE READ

Every number here is an estimate meant to help you decide when to visit the air pump. It is not a measurement and not a replacement for one.

• Your vehicle's door placard is the authority on target pressure • Confirm with a gauge before adjusting anything • Pressure readings only compare properly on cold tires — parked three hours or more, before driving. Driving heats tires and raises the reading • Your phone measures nothing; the app cannot see your actual tires

PRIVACY

Your location is used only to look up the temperature nearby, rounded before it is sent, and never stored or shared. Your vehicles stay on your device.

ONE PURCHASE

Buy it once and everything is included. No subscription, no in-app purchases, no ads.