tiresizeinches.com

Same 20 in wheel · side by side

275/65R20 vs 305/55R20

First size

mm, 115–395
% of width
inches

Second size

mm, 115–395
% of width
inches

Comparing 275/65R20 · 305/55R20. Change any field and both follow.

Difference in overall diameter

−2.54%

305/55R20 is 0.87 in shorter than 275/65R20 (−2.54%) and 1.18 in wider; at an indicated 60 mph you are doing 58.5 mph.

275/65R20 and 305/55R20 laid over each other at one scale, with the gap enlargedTwo circles drawn at one scale and sharing a center: the solid ring is 275/65R20 at 34.07 in overall, the dashed ring is 305/55R20 at 33.21 in. A detail view beside them shows the same two edges enlarged, with the gap between them dimensioned at 0.87 in.0.87 inDETAIL — ENLARGED275/65R20 · 34.07 in305/55R20 · 33.21 in
Both overall diameters at one scale, sharing a center. The detail beside them enlarges the one place they differ, and its dimension is the difference the table below states.

The difference, one row at a time

275/65R20 and 305/55R20, one measurement per row; the difference is 305/55R20 minus 275/65R20
Measure­ment 275/65R20 305/55R20 Differ­ence
Overall diameter34.07 in33.21 in−0.87 in · −2.54%
Section width10.83 in12.01 in+1.18 in
Sidewall height7.04 in6.60 in−0.43 in
Circumference107.05 in104.33 in−2.72 in
Revolutions per mile591.9607.3+15.4

Other pairs with one of these two in them

Each size on its own