305/35R20 tire size
305/35R20 is a metric size: 28.4" tall, 12.0" wide, on a 20" rim — about a 28.5x12.00R20. The sidewall is 4.2" and the tire turns 710 times per mile.
305/35R20 specs
| Overall diameter (height) | 28.41" · 722 mm |
|---|---|
| Section width | 12.01" · 305 mm |
| Sidewall height | 4.20" · 107 mm (35% of width) |
| Rim diameter | 20" |
| Circumference | 89.24" · 2.267 m |
| Revolutions per mile | 710 (441 per km) |
| Inch (flotation) equivalent | 28.5x12.00R20 |
Equivalent sizes on a 20" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 245/45R20 common | 28.68" | +0.97% | -60 mm | 60.6 mph | compare → |
| 255/45R20 common | 29.04" | +2.22% | -50 mm | 61.3 mph | compare → |
| 275/40R20 common | 28.66" | +0.90% | -30 mm | 60.5 mph | compare → |
| 245/40R20 common | 27.72" | -2.43% | -60 mm | 58.5 mph | compare → |
| 245/50R20 common | 29.65" | +4.37% | -60 mm | 62.6 mph | compare → |
| 275/45R20 common | 29.74" | +4.71% | -30 mm | 62.8 mph | compare → |
| 255/35R20 common | 27.03" | -4.85% | -50 mm | 57.1 mph | compare → |
| 255/40R20 common | 28.03" | -1.32% | -50 mm | 59.2 mph | compare → |
| 275/35R20 common | 27.58" | -2.91% | -30 mm | 58.3 mph | compare → |
| 265/45R20 common | 29.39" | +3.47% | -40 mm | 62.1 mph | compare → |
| 285/35R20 common | 27.85" | -1.94% | -20 mm | 58.8 mph | compare → |
| 315/35R20 common | 28.68" | +0.97% | +10 mm | 60.6 mph | compare → |
| 265/35R20 common | 27.30" | -3.88% | -40 mm | 57.7 mph | compare → |
| 305/30R20 | 27.20" | -4.23% | 0 mm | 57.5 mph | compare → |
| 295/40R20 | 29.29" | +3.12% | -10 mm | 61.9 mph | compare → |
| 295/35R20 | 28.13" | -0.97% | -10 mm | 59.4 mph | compare → |
| 285/40R20 | 28.98" | +2.01% | -20 mm | 61.2 mph | compare → |
| 235/50R20 | 29.25" | +2.98% | -70 mm | 61.8 mph | compare → |
| 235/45R20 | 28.33" | -0.28% | -70 mm | 59.8 mph | compare → |
| 265/40R20 | 28.35" | -0.21% | -40 mm | 59.9 mph | compare → |
| 305/40R20 | 29.61" | +4.23% | 0 mm | 62.5 mph | compare → |
| 315/30R20 | 27.44" | -3.40% | +10 mm | 58.0 mph | compare → |
| 235/40R20 | 27.40" | -3.53% | -70 mm | 57.9 mph | calculate → |
| 335/30R20 | 27.91" | -1.73% | +30 mm | 59.0 mph | calculate → |
| 325/30R20 | 27.68" | -2.56% | +20 mm | 58.5 mph | calculate → |
| 345/30R20 | 28.15" | -0.90% | +40 mm | 59.5 mph | calculate → |
| 215/45R20 | 27.62" | -2.77% | -90 mm | 58.3 mph | calculate → |
| 325/35R20 | 28.96" | +1.94% | +20 mm | 61.2 mph | calculate → |
| 195/50R20 | 27.68" | -2.56% | -110 mm | 58.5 mph | calculate → |
| 225/40R20 | 27.09" | -4.64% | -80 mm | 57.2 mph | calculate → |
| 29x15.00R20 | 29.00" | +2.09% | +76 mm | 61.3 mph | calculate → |
| 29x18.00R20 | 29.00" | +2.09% | +152 mm | 61.3 mph | calculate → |
| 175/55R20 | 27.58" | -2.91% | -130 mm | 58.3 mph | calculate → |
| 145/65R20 | 27.42" | -3.47% | -160 mm | 57.9 mph | calculate → |
| 155/60R20 | 27.32" | -3.81% | -150 mm | 57.7 mph | calculate → |
| 195/55R20 | 28.44" | +0.14% | -110 mm | 60.1 mph | calculate → |
| 225/45R20 | 27.97" | -1.52% | -80 mm | 59.1 mph | calculate → |
| 155/65R20 | 27.93" | -1.66% | -150 mm | 59.0 mph | calculate → |
| 165/60R20 | 27.80" | -2.15% | -140 mm | 58.7 mph | calculate → |
| 175/70R20 | 29.65" | +4.37% | -130 mm | 62.6 mph | calculate → |
Plus / minus sizing: 19" and 21" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 235/50R19 common | 28.25" | -0.54% | -70 mm | 59.7 mph | compare → |
| 245/50R19 common | 28.65" | +0.85% | -60 mm | 60.5 mph | compare → |
| 275/35R21 common | 28.58" | +0.61% | -30 mm | 60.4 mph | compare → |
| 265/35R21 | 28.30" | -0.36% | -40 mm | 59.8 mph | compare → |
| 325/30R21 | 28.68" | +0.96% | +20 mm | 60.6 mph | compare → |
| 315/30R21 | 28.44" | +0.12% | +10 mm | 60.1 mph | compare → |
| 305/30R21 | 28.20" | -0.71% | 0 mm | 59.6 mph | compare → |
| 295/40R19 | 28.29" | -0.40% | -10 mm | 59.8 mph | compare → |
| 265/45R19 | 28.39" | -0.06% | -40 mm | 60.0 mph | calculate → |
| 345/35R19 | 28.51" | +0.36% | +40 mm | 60.2 mph | calculate → |
| 145/80R19 | 28.13" | -0.96% | -160 mm | 59.4 mph | calculate → |
Try another size against 305/35R20
Questions
What size is 305/35R20 in inches?
305/35R20 is about 28.4" tall and 12.0" wide on a 20-inch rim — roughly a 28.5x12.00R20 in inch sizing.
What does 305/35R20 mean?
305 mm section width, sidewall 35% of the width (4.20"), radial construction, 20-inch rim.
What tire sizes are equivalent to 305/35R20?
On the same 20" rim, within 3% of the diameter: 195/55R20 (+0.14%), 265/40R20 (-0.21%), 235/45R20 (-0.28%), 275/40R20 (+0.90%), 345/30R20 (-0.90%), 245/45R20 (+0.97%).
How many revolutions per mile does a 305/35R20 tire make?
About 710 revolutions per mile (circumference 89.2").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.