Tire Pressure by Temp
Winter drops the temperature and your tire pressure with it — see the estimate before you drive.
Download on the App Store
Screenshots










Features
Today's estimate from your placard number
Enter the pressure printed on your door placard once, along with the temperature it was set at. From then on the app estimates what your tires would read at the current temperature, and roughly how much air it would take to get back to your target.
The temperature, fetched for you
The current temperature comes from your local forecast automatically, so there is nothing to type in each morning. Your coordinates are rounded before they are sent, and neither stored nor shared.
A heads-up the night before
When a cold morning is on the way, an optional evening notification shows you the estimate — so a deep freeze isn't a surprise in the driveway.
Every vehicle in the driveway
Car, truck, motorcycle, bicycle, camper van, trailer — add as many as you like. Front and rear axles can carry different targets, and each vehicle keeps its own unit: psi, kPa or bar.
Home Screen widget
Small and Medium widgets show the morning estimate without opening the app. A glance on the way out the door is usually all you need.
The "what if" slider
Drag the temperature slider to see the estimate at −30 °C, or at 20 °C. Useful when the forecast swings thirty degrees in a week, which it does.
No sensors, no hardware
Nothing to buy, mount or pair. No valve-stem sensors, no Bluetooth. Just the number from your placard and the temperature outside.
The math is shown, not hidden
The estimate uses the ideal gas law at constant volume, converting gauge pressure to absolute pressure before applying the ratio. The settings screen shows the formula so you can check the work yourself.
One purchase, everything on your device
A single purchase — no subscription, no in-app purchases, no ads. No account to create, no tracking, and your vehicles never leave your iPhone.
Tire pressure falls as the air gets colder, and a Canadian winter makes that impossible to ignore. 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 deep freeze isn't a surprise
• Temperature slider to explore "what if it drops to -30°C?"
• Home Screen widget shows the morning estimate without opening the app
BUILT FOR EVERY VEHICLE YOU OWN
Add as many as you like: car, truck, 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 on one vehicle and kPa or bar on 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.