Best 315/40R21 tires

70 rated tires available in this size, scored on dry, wet, snow, comfort and wear.

Top pick in 315/40R21

1,852 owner reviews · 31 tests

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Every rated 315/40R21 tire, by season

Ranked by our Relative score, weighed against how many reviews and tests stand behind it.

How scores work

Relative score: 0–100. Blends road tests (60%) and owner reviews (40%) category by category, the same way on every TireWheelGuide page. With only one of the two, the missing half is estimated from it, so the score stays closer to average. It needs at least one road test or five owner reviews.
Ranking: The score already allows for how much stands behind it: with only a few reviews or tests a tire stays near the typical score. Among similar scores, newer tires rank higher and tires replaced by a newer generation lower.

Rank by

23 more rated tires in this size are listed on their brand pages.

11 more rated tires in this size are listed on their brand pages.

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Revolutions per mile: how many times the tire turns in one mile, the count your speedometer is calibrated to.

A tire fits a range of rim widths. Too narrow or too wide and the sidewall changes shape.

Minimum

8.5″

Ideal

10″

Maximum

11″

The rim diameter is fixed at 21″; only the width can change. Rims are usually 70–90% as wide as the tire’s 12.4″ section width.

Fitted from the factory on rims: 21x10.5, 21x11.

Some factory fitments sit outside that range: 21x11.5. Check the rim width approved for your car before you buy.

Fitted from the factory on at least one trim. Models with the most trims and years in this size come first.

Parameter	Meaning
315	The first number is the section width — 315 mm, or about 12.4 inches across the widest part of the tire.
40	The second number is the aspect ratio: sidewall height as a percentage of width. At 40%, the sidewall is about 126 mm tall.
R21	R means radial construction, which nearly all modern tires use. The number is the rim diameter in inches — this tire fits a 21-inch wheel.