From 2022 season, F1 cars use 18-inch tyres provided by Pirelli who is an official supplier since 2011 and they have increased in diameter by 65 mm (now 725 mm).
2022 Formula One Technical Regulation Article 10.8.1 – Tyre Dimensions
a. Tyre width and diameter will be measured parallel to and in a plane perpendicular to respectively the wheel rotation axis with new tyres fitted and inflated to 1.4 bar.
b. Tyre width must lie between 345mm and 375mm when fitted to the front of the car and between 440mm and 470mm when fitted to the rear.
c. Tyre diameter must not exceed 725mm when for dry-weather tyres or 735mm for wet weather tyres.
Tyre blankets are permitted, but the maximum temperature has been reduced to 70 °C for both front and rear tyres (2021 – front 100 °C, rear 80 °C)
2022 Formula One Technical Regulation Article 10.8.4 – Treatment of tyres
a. Tyres may only be inflated with air or nitrogen.
b. Any process the intent of which is to reduce the amount of moisture in the tyre and/or in its inflation gas is forbidden.
c. A complete wheel must contain a single fixed internal gas volume. No valves, bleeds or permeable membranes are permitted other than to inflate or deflate the tyre whilst the car is stationary.
d. The only permitted type of tyre heating devices are blankets that comply with the design prescriptions listed in Article 10.8.5.