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2023 Porsche 911 Tire Fitment

3 factory tire sizes across trims — select yours below.

Trim fitment

Trim(s) OEM size
Carrera 235/40ZR19 Specs →
Carrera S 245/35ZR20 Specs →
Turbo 255/35ZR20 Specs →
OEM size
235/40ZR19
Diameter
26.4″
Sidewall
3.7″
Revs / mile
764

About 2023 Porsche 911 fitment

The 2023 Porsche 911 Carrera ships from the factory with 235/40ZR19 tires, giving a 26.40″ overall diameter and 764 revs per mile. This is the reference size the factory speedometer, odometer, ABS, and TPMS were calibrated against, so any replacement tire should stay close to 26.40″ to preserve correct readings. This model year ships in multiple configurations with different OEM tire sizes (235/40ZR19, 245/35ZR20, 255/35ZR20), so confirm your exact trim badge before ordering. The smallest recommended upsize is 225/45R19 — a 2.16% diameter change — which keeps the speedometer inside factory tolerance while adding marginal ride height and sidewall compliance. The most aggressive option shown, 235/35R20, runs 0.28% taller and will likely need clearance checking on stock suspension. For a direct replacement, look for brands offering 235/40ZR19 in all-season, highway, or terrain-appropriate compounds — the OEM spec typically emphasizes fuel economy and tread life over grip, so aftermarket replacements often unlock better wet performance or off-road capability at similar cost. Before committing to an upsize, confirm wheel-well clearance at full steering lock and suspension compression, and verify the chosen size does not conflict with snow chains, tire-fit sensors, or any lift-kit hardware already installed.

Upsize options

Size Diameter Δ vs OEM
225/45R19 26.97″ +2.16% Details →
255/35R20 27.03″ +2.37% Details →
255/40R19 27.03″ +2.39% Details →
245/35R20 26.75″ +1.33% Details →
245/40R19 26.72″ +1.19% Details →
235/45R19 27.33″ +3.50% Details →
265/40R19 27.35″ +3.58% Details →
235/35R20 26.48″ +0.28% Details →

Check speedometer error before upsizing

Type to search · try 275/65R18 or "33" for inch aliases
Common upsizes from 235/40ZR19:
Don't know your stock size? Load it by vehicle:

235/40ZR19

Diameter
26.4″ / 670.6mm
Section Width
9.25
Sidewall
3.7″ / 94mm
Circumference
82.94
Revs/Mile
764
See tires in 235/40ZR19

225/45R19

Diameter
26.97″ / 685.1mm
Section Width
8.86
Sidewall
3.99″ / 101.25mm
Circumference
84.74
Revs/Mile
748
See tires in 225/45R19
235/40ZR19 · 26.4225/45R19 · 26.97

Speedometer & Diameter Impact

Diameter Change
+2.16%
Sidewall Change
+0.29″
Revs/Mile Δ
-16
mph

At an indicated 60 mph, your actual speed is 61.3 mph (98.65 km/h). Your speedometer reads 2.16% low versus actual speed.

Speedometer impact if you upsize from 235/40ZR19

Porsche 911 — other model years