265/30R20
Overall diameter 667 mm
265/30R20 — 667 mm tall, and what it swaps with
265/30R20 is 265 mm wide with a 30% sidewall on a 20-inch wheel. That sidewall is 79.5 mm, so the tyre stands 667 mm tall and turns 477.2 times per kilometre.
- Section width
- 265 mm
- Aspect ratio
- 30 %
- Wheel size
- 20 in (508 mm)
- Sidewall height
- 79.5 mm
- Overall diameter
- 667 mm (26.26 in)
- Circumference
- 2095.4 mm
- Turns per km
- 477.2
Sizes you can swap to
Only sizes whose overall diameter stays within 3% are listed. A different diameter covers a different distance per turn, and that gap becomes speedometer error.
205/70R15668 mm · +0.15% you go faster265/35R19668.1 mm · +0.16% you go faster215/55R17668.3 mm · +0.19% you go faster235/45R18668.7 mm · +0.25% you go faster215/60R16664.4 mm · -0.39% you go slower235/40R19670.6 mm · +0.54% you go faster225/40R19662.6 mm · -0.66% you go slower215/50R18672.2 mm · +0.78% you go faster235/35R20672.5 mm · +0.82% you go faster255/40R18661.2 mm · -0.87% you go slower205/65R16672.9 mm · +0.88% you go faster255/35R19661.1 mm · -0.88% you go slower
Same profile, different width
Other sizes for this wheel
20-inch wheels
235/35R20 672.5mm235/45R20 719.5mm235/55R20 766.5mm245/30R20 655mm245/35R20 679.5mm245/40R20 704mm245/45R20 728.5mm245/50R20 753mm255/30R20 661mm255/35R20 686.5mm255/40R20 712mm255/45R20 737.5mm255/50R20 763mm265/30R20 667mm265/35R20 693.5mm265/40R20 720mm265/45R20 746.5mm265/50R20 773mm275/30R20 673mm275/35R20 700.5mm275/40R20 728mm275/45R20 755.5mm275/55R20 810.5mm285/30R20 679mm285/35R20 707.5mm285/40R20 736mm285/50R20 793mm295/30R20 685mm295/35R20 714.5mm305/30R20 691mm315/35R20 728.5mm
How the code reads
The 205 is millimetres, the 55 is a percentage of that width, and only the 16 is inches. The R stands for radial construction.
How to read this
- The first three digits are the width in mm, the middle two are the aspect ratio in percent, the last two the wheel in inches.
- Sidewall height = width × aspect ÷ 100. For 205/55 that is 112.75 mm.
- Overall diameter = wheel diameter + twice the sidewall. A 16-inch wheel is 406.4 mm.
- Once the diameter shifts by more than 3%, the speedometer and odometer drift by the same amount.
Frequently asked questions
Q. What is the overall diameter of 265/30R20?
667 mm — the 508 mm wheel plus the 79.5 mm sidewall at top and bottom.
Q. How many turns per kilometre does 265/30R20 make?
Its circumference is 2095.4 mm, so 477.2 turns.
Q. What can I swap it for?
12 sizes stay within 3% of its diameter — the closest is 205/70R15 at 668 mm.
Q. Why is the sidewall 79.5 mm?
Because it is 30% of the 265 mm width. The aspect ratio is a proportion of the width, not a length.