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Compare two sizes › Tire sizes › 195/65R15

195/65R15: 634.5 mm (24.98 in) tall

A 195/65R15 tire is 195 mm wide with a 126.75 mm sidewall on a 15-inch rim. It turns 807.4 times per mile. Below: every dimension, a drawing to scale, and the 28 sizes within ±3 % of its diameter on 14, 15 and 16 in rims, with what the speedometer would read on each.

Every dimension

Measuremminches
Section widthsidewall to sidewall, as printed195.0 mm7.68 in
Sidewall height65 % of the width126.75 mm4.99 in
Rim diameterbead seat, as printed381.0 mm15 in
Overall diameterrim + two sidewalls634.5 mm24.98 in
Circumferenceπ × diameter1,993.3 mm78.48 in
Revolutions per mileunloaded, geometric807.4
Revolutions per kmunloaded, geometric501.7

Nominal figures for a new, unloaded tire. Under a car's weight it squashes and turns roughly 2–3 % more often per mile; the maker's datasheet figure is measured and wins.

What 195/65R15 means

195
Section width in millimetres (7.68 in), sidewall to sidewall. It is measured on the rim width the tire standard lists for that size; on a wider or narrower rim it changes by roughly 5 mm per half inch.
65
Aspect ratio: the sidewall is 65 % as tall as the tire is wide — 195 × 65 ÷ 100 = 126.75 mm. It is a percentage, not a height.
R
Radial construction (not "radius"). Written ZR, it is a radial rated above 240 km/h.
15
Rim diameter in inches (381.0 mm): the wheel this tire mounts on.
after
The load index and speed symbol follow the size (for example 195/65R15 91V or 94W XL). The same size is sold with several; type yours into the calculator below to decode it.

Drawn to scale

634.5 mmsidewall126.75 mmrim 15 inSideFront195 mm24.98 in tallwide
195/65R15 from the side and tread-on, both at the same scale. The yellow bar is the sidewall; the grey disc is the 15-inch wheel.

Closest swap

On the same rim, 215/60R15 is nearest in diameter: +0.7 %. Going up to a 16-inch rim, 175/65R16 is nearest: −0.1 %, so the speedometer reads +0.1 %; at an indicated 60 mph you would do 59.9 mph.

Sizes within ±3 % of 195/65R15

Every size in the grid (widths 175–215 mm in 10 mm steps, aspect ratios 25–80 in steps of 5) whose overall diameter is within ±3 % of 634.5 mm. ±3 % is a rule of thumb many tire fitters use, not a law. The “really doing” column assumes the speedometer was right on 195/65R15: it is your true speed when the speedometer shows 60 mph (and, below it, 100 km/h). Not every size here is made by every maker, and a size being close in diameter says nothing about clearance, load rating or what the car maker approves. Tap a size to load it into the calculator.

Same 15-inch rim 8

SizeDiametervs 195/65R15Really doing
215/60R15639.0 mm25.16 in+0.7 %+4.5 mm60.4 mph100.7 km/h
185/70R15640.0 mm25.20 in+0.9 %+5.5 mm60.5 mph100.9 km/h
205/60R15627.0 mm24.69 in−1.2 %−7.5 mm59.3 mph98.8 km/h
175/70R15626.0 mm24.65 in−1.3 %−8.5 mm59.2 mph98.7 km/h
175/75R15643.5 mm25.33 in+1.4 %+9.0 mm60.9 mph101.4 km/h
185/65R15621.5 mm24.47 in−2.0 %−13.0 mm58.8 mph98.0 km/h
205/65R15647.5 mm25.49 in+2.0 %+13.0 mm61.2 mph102.0 km/h
215/55R15617.5 mm24.31 in−2.7 %−17.0 mm58.4 mph97.3 km/h

One inch smaller: 14-inch rim 9

SizeDiametervs 195/65R15Really doing
215/65R14635.1 mm25.00 in+0.1 %+0.6 mm60.1 mph100.1 km/h
175/80R14635.6 mm25.02 in+0.2 %+1.1 mm60.1 mph100.2 km/h
185/75R14633.1 mm24.93 in−0.2 %−1.4 mm59.9 mph99.8 km/h
195/70R14628.6 mm24.75 in−0.9 %−5.9 mm59.4 mph99.1 km/h
205/70R14642.6 mm25.30 in+1.3 %+8.1 mm60.8 mph101.3 km/h
205/65R14622.1 mm24.49 in−2.0 %−12.4 mm58.8 mph98.0 km/h
195/75R14648.1 mm25.52 in+2.1 %+13.6 mm61.3 mph102.1 km/h
175/75R14618.1 mm24.33 in−2.6 %−16.4 mm58.4 mph97.4 km/h
185/80R14651.6 mm25.65 in+2.7 %+17.1 mm61.6 mph102.7 km/h

Plus one: 16-inch rim 11

SizeDiametervs 195/65R15Really doing
175/65R16633.9 mm24.96 in−0.1 %−0.6 mm59.9 mph99.9 km/h
205/55R16631.9 mm24.88 in−0.4 %−2.6 mm59.8 mph99.6 km/h
195/60R16640.4 mm25.21 in+0.9 %+5.9 mm60.6 mph100.9 km/h
185/60R16628.4 mm24.74 in−1.0 %−6.1 mm59.4 mph99.0 km/h
215/55R16642.9 mm25.31 in+1.3 %+8.4 mm60.8 mph101.3 km/h
185/65R16646.9 mm25.47 in+2.0 %+12.4 mm61.2 mph102.0 km/h
215/50R16621.4 mm24.46 in−2.1 %−13.1 mm58.8 mph97.9 km/h
195/55R16620.9 mm24.44 in−2.1 %−13.6 mm58.7 mph97.9 km/h
175/70R16651.4 mm25.65 in+2.7 %+16.9 mm61.6 mph102.7 km/h
205/60R16652.4 mm25.69 in+2.8 %+17.9 mm61.7 mph102.8 km/h
175/60R16616.4 mm24.27 in−2.9 %−18.1 mm58.3 mph97.1 km/h

Compare 195/65R15 with any size

Try:

Working it out…

Speedometer error

The speedometer counts wheel turns and assumes the current tire.

Speedometer showsYou are really doingDifference

Both to scale

Side view (left pair) and tread-on front view (right pair), all four at the same scale. The dashed ring on the new tire is the current tire's outline.

What the codes say

Load index and speed rating tables (ISO 4000-1 / ETRTO)

Side by side

MeasureCurrentNewDifference

The sums for 195/65R15

sidewall = 195 × 65 ÷ 100 = 126.75 mm diameter = 15 × 25.4 + 2 × 126.75 = 634.5 mm circumference = π × 634.5 = 1,993.3 mm revs per mile = 1,609,344 ÷ 1,993.3 = 807.4 revs per km = 1,000,000 ÷ 1,993.3 = 501.7

Speedometer error is the ratio of the two diameters: true speed = shown speed × new diameter ÷ 195/65R15 diameter. Fitting 175/65R16 (633.9 mm) in place of 195/65R15, an indicated 100 km/h is really 99.9 km/h, and the odometer is off by the same proportion.

Why these ten sizes

We found no public list of the most-sold tire sizes that we are allowed to reuse, so the ten size pages follow a stated rule instead. Take two popular 17-inch sizes, 225/45R17 and 215/55R17. For each rim from 15 to 19 inches, pick the size with the closest overall diameter among widths 185 + 10 × (rim − 15) to 215 + 10 × (rim − 15) mm and aspect ratios 35–65. That is the "plus sizing" ladder: each inch of rim gains about 10 mm of width and loses sidewall, and the diameter stays put. 195/65R15 is on the 225/45R17 ladder, 0.2 mm from its diameter.

What this page cannot tell you

  • Whether a size is right for your car. Clearance to struts, arches and brake calipers, wheel width and offset, steering lock and suspension travel decide that, and none of them is in the size code. Start from the sizes the car maker lists (door-jamb placard, handbook, registration papers), then check the physical clearance.
  • Load capacity. An alternative size must carry at least the load index and speed rating the car maker specifies; a narrower or lower-profile tire often has a lower load index in the same construction, so check the XL / reinforced version.
  • Exact real-world size. Makers build to a tolerance of a few percent, and a new tire with 8 mm of tread is about 13 mm taller than one worn to 1.6 mm.
  • Your speedometer's own error. Under UN ECE Regulation 39 a speedometer must never read below true speed and may read up to 10 % + 4 km/h high, so most cars already over-read a little. A taller tire eats into that margin.

Other sizes