tiresizeinches.com

Metric tire size · 18 in wheel

305/70R18 tire size in inches and millimeters

mm, 115–395
% of width
inches

Reading 305/70R18. Change any field and the gauge follows.

Overall diameter

34.81in

A 305/70R18 tire stands 34.81 in (884.2 mm) tall, which makes it a 35-inch tire, 0.19 in under.

Section width
12.01 in305 mm
Sidewall
8.41 in213.5 mm
Wheel
18 in457.2 mm
305/70R18 drawn to scaleA 305/70R18 tire drawn to scale, seen from the side and head-on at one scale. Four dimension lines label the overall diameter 34.81 in, the wheel diameter 18 in, the sidewall height 8.41 in and the section width 12.01 in. Every one of those values is stated in text on this page.34.81 in18 in wheel8.41 in12.01 in
Drawn to scale. Hover or focus a row in the equivalents table to lay that size over this one.

Full specification

305/70R18 — one measurement per row, in both unit systems
Dimension Inchesin Millimetersmm
Overall diameter34.81884.2
Section width12.01305.0
Sidewall height8.41213.5
Wheel diameter18.00457.2
Circumference109.362,777.8
305/70R18 — the quantities that are not one measurement in two units
QuantityValueUnit
Revolutions579.4per mile
Revolutions360.0per kilometer
Aspect ratio70% of section width
ConstructionRradial

Sizes that will do the same job

Where every equivalent size falls inside the tolerance bandA horizontal scale running from three percent under to three percent over the 305/70R18 overall diameter of 34.81 in. Each of the 10 sizes in the table is drawn as a tick at its own difference; the pointer marks 285/75R18 at +0.06%. Every plotted value is a row of the table below.−3−2−10123SHORTERTALLER285/75R18 · +0.06%
The scale is percent difference in overall diameter against 34.81 in. Every mark is a row of the table below, at its own distance from it.

10 sizes in this table are within ±3% of 34.81 in. A positive difference is taller than 305/70R18; every sign is printed as well as colored.

The most searched equivalents of 305/70R18, 10 listed, sorted by how far each is from 34.81 in. Open a row for its section width and speed.
Size Overall diameterin Difference vs 305/70R18% of diameter, then inches Actual speedmph at an indicated 60
34.83 +0.06% +0.02 in 60.0
34.69 −0.34% −0.12 in 59.8
34.63 −0.51% −0.18 in 59.7
35.32 +1.47% +0.51 in 60.9
34.26 −1.58% −0.55 in 59.0
35.36 +1.58% +0.55 in 61.0
34.24 −1.64% −0.57 in 59.0
35.42 +1.75% +0.61 in 61.1
34.12 −1.98% −0.69 in 58.8
34.06 −2.15% −0.75 in 58.7

The next sizes up and down

One width step and one profile step either side of 305/70R18, on the same wheel.
Size Overall diameterdifference % and inches Section widthvs 305/70R18, then mph at an indicated 60
narrower295/70R18 34.26−1.58% −0.55 in −0.39 in59.0 mph actual
wider315/70R18 35.36+1.58% +0.55 in +0.39 in61.0 mph actual
lower profile305/65R18 33.61−3.45% −1.20 in 0.00 in57.9 mph actual
taller profile305/75R18 36.01+3.45% +1.20 in 0.00 in62.1 mph actual