Truck Tire Size Calculator
Compare lifted, semi and commercial truck tire sizes in metric (295/75R22.5), numeric (11R22.5) and flotation (35×12.50R17) formats. See the diameter change, speedometer error and effective gear ratio, with a semi truck tire size chart below.
Quick Answer
- 295/75R22.5 calculates to 39.9″ tall and 505 revs per mile. Bridgestone's 2023 data book lists 39.5–41.0″ for the models it sells.
- 11R22.5 has no aspect ratio, so the calculator estimates 41.4″ (487 revs per mile) against 40.6–42.4″ in the data book. That is +1.50″ (+3.75%) compared with 295/75R22.5.
- Bridgestone lists 295/75R22.5, 275/70R22.5 and 225/70R19.5 among the most common truck sizes. Speedometer error and effective gear ratio change by the same percentage as the diameter.
Quick presets: sizes listed in the same owner's manual or spec sheet
Truck Tire Size Guide
Truck tire sizes by model, LT vs P-metric tires, load ranges and plus-sizing explained.
Semi Truck Tire Size Chart
Bridgestone's semi truck tire size guide says the most common truck tire sizes include 295/75R22.5, 275/70R22.5 and 225/70R19.5. The chart below is from Bridgestone's 2023 Truck Tire Data Book. Each value is a range across the Bridgestone and Firestone models listed for that size and load range.
Metric sizes and their inch-format equivalents
| Metric size | Inch format | Typical use (Bridgestone) |
|---|---|---|
| 295/75R22.5 | 11R22.5 | Drive and trailer, long haul. Listed as its most common size. |
| 275/80R22.5 | 11R22.5 | Steer and drive |
| 285/75R24.5 | 11R24.5 | Drive, heavy haul |
| 255/70R22.5 | 10R22.5 | Trailer, regional |
Diameter, width, load and weight by size
| Rims | Tire size | Load range | Load index | Overall diameter | Overall width | Max load, single | Max load, dual | Weight | Revs/mile |
|---|---|---|---|---|---|---|---|---|---|
| 22.5 in. and 24.5 in. rims | 295/75R22.5 | G | 144/141 | 39.5–41.0" | 10.9–11.7" | 6,175 lb @ 110 psi | 5,675 lb @ 110 psi | 94–129 lbs | 506–525 |
| 22.5 in. and 24.5 in. rims | 295/75R22.5 | H | 149/146 | 40.3" | 11.4" | 7,160 lb @ 120 psi | 6,610 lb @ 120 psi | 114–118 lbs | 515–516 |
| 22.5 in. and 24.5 in. rims | 285/75R24.5 | G | 144/141 | 40.8–42.2" | 10.7–11.4" | 6,175 lb @ 110 psi | 5,675 lb @ 110 psi | 103–138 lbs | 492–509 |
| 22.5 in. and 24.5 in. rims | 285/75R24.5 | H | 147/144 | 41.3" | 11.4" | 6,780 lb @ 120 psi | 6,175 lb @ 120 psi | 118 lbs | 503 |
| 22.5 in. and 24.5 in. rims | 315/80R22.5 | L | — | 42.6–42.9" | 12.4–12.8" | 10,000 lb @ 130 psi | 9,090 lb @ 130 psi | 144–168 lbs | 484–488 |
| 22.5 in. and 24.5 in. rims | 11R22.5 | G | 144/142 | 40.6–42.4" | 10.8–11.6" | 6,175 lb @ 105 psi | 5,840 lb @ 105 psi | 103–143 lbs | 490–512 |
| 22.5 in. and 24.5 in. rims | 11R22.5 | H | 146/143 | 41.1–42.6" | 10.8–11.6" | 6,610 lb @ 120 psi | 6,005 lb @ 120 psi | 116–143 lbs | 487–505 |
| 22.5 in. and 24.5 in. rims | 11R24.5 | G | 146/143 | 42.8–44.2" | 10.7–11.6" | 6,610 lb @ 105 psi | 6,005 lb @ 105 psi | 109–143 lbs | 470–486 |
| 22.5 in. and 24.5 in. rims | 11R24.5 | H | 149/146 | 43.1–44.6" | 10.8–11.6" | 7,160 lb @ 120 psi | 6,610 lb @ 120 psi | 124–157 lbs | 465–482 |
| 22.5 in. and 24.5 in. rims | 255/70R22.5 | H | 140/137 | 36.3–37.3" | 9.8–10.4" | 5,510 lb @ 120 psi | 5,070 lb @ 120 psi | 87–102 lbs | 557–572 |
| 22.5 in. and 24.5 in. rims | 275/70R22.5 | J | 148/145 | 38.0–38.5" | 10.7–10.9" | 6,940 lb @ 120 psi | 6,395 lb @ 120 psi | 110–122 lbs | 540–547 |
| 22.5 in. and 24.5 in. rims | 385/65R22.5 | J | 158 | 42.9–43.4" | 15.3–15.5" | 9,370 lb @ 120 psi | — | 173–196 lbs | 482–484 |
| 22.5 in. and 24.5 in. rims | 385/65R22.5 | L | 160 | 42.8" | 15.3" | 9,920 lb @ 130 psi | — | 166 lbs | 485 |
| 22.5 in. and 24.5 in. rims | 445/50R22.5 | L | 161 | 39.2–39.9" | 17.7–19.4" | 10,200 lb @ 120 psi | — | 152–173 lbs | 524–533 |
| 22.5 in. and 24.5 in. rims | 455/55R22.5 | M | 166 | 41.9" | 18.2" | 11,700 lb @ 130 psi | — | 215–217 lbs | 496–499 |
| 19.5 in. rims | 225/70R19.5 | F | 125/123 | 32.2–32.5" | 8.5–8.7" | 3,640 lb @ 95 psi | 3,415 lb @ 95 psi | 66–67 lbs | 639–644 |
| 19.5 in. rims | 225/70R19.5 | G | 128/126 | 32.2–32.5" | 8.5–8.7" | 3,970 lb @ 110 psi | 3,750 lb @ 110 psi | 66–70 lbs | 639–644 |
| 19.5 in. rims | 245/70R19.5 | F | 129/127 | 33.3" | 9.3" | 4,080 lb @ 95 psi | 3,860 lb @ 95 psi | 82 lbs | 623 |
| 19.5 in. rims | 245/70R19.5 | G | 133/131 | 33.3" | 9.3" | 4,540 lb @ 110 psi | 4,300 lb @ 110 psi | 82 lbs | 623 |
| 19.5 in. rims | 245/70R19.5 | H | 136/134 | 33.3–33.5" | 9.3–9.7" | 4,940 lb @ 120 psi | 4,675 lb @ 120 psi | 75–82 lbs | 620–623 |
| 19.5 in. rims | 265/70R19.5 | G | 140/138 | 34.1" | 10.0" | 5,510 lb @ 110 psi | 5,205 lb @ 110 psi | 84 lbs | 609 |
Load index is derived from the listed single and dual loads using the data book's load index table. Michelin's Truck Tire Data Book (20th edition) gives the same maximum loads for the sizes both list, but inflation pressure can differ by maker for the same load (Michelin lists 275/70R22.5 load range J at 130 psi, Bridgestone at 120 psi), so use the pressure in your own tire maker's data book.
Diameter and width in millimetres
| Tire size | Overall diameter | Overall width |
|---|---|---|
| 295/75R22.5 | 1,003–1,041 mm | 277–297 mm |
| 11R22.5 | 1,031–1,077 mm | 274–295 mm |
| 285/75R24.5 | 1,036–1,072 mm | 272–290 mm |
| 11R24.5 | 1,087–1,123 mm | 272–295 mm |
| 275/70R22.5 | 965–978 mm | 272–277 mm |
| 255/70R22.5 | 922–947 mm | 249–264 mm |
| 225/70R19.5 | 818–826 mm | 216–221 mm |
| 445/50R22.5 | 996–1,013 mm | 450–493 mm |
Converted from the data book ranges above (1 in = 25.4 mm). Michelin's Truck Tire Service Manual says tires mounted in dual must be matched to within ¼ inch in diameter, and that tandem drive axles without an inter-axle differential, or with it locked out, need closely matched tires.
Truck Tire Diameter and Revolutions per Mile
Overall diameter, section width, sidewall height, circumference and revolutions per mile for common truck sizes. Semi sizes are the Bridgestone 2023 data book ranges, and the flotation and metric light truck rows are calculated from the size code.
| Tire Size | OD | Sec. Width | Sidewall | Circ. | Rev/Mile | Load Range | Source |
|---|---|---|---|---|---|---|---|
| 295/75R22.5 | 39.5–41.0" | 10.9–11.7" | 8.71" (calc.) | n/a | 506–525 | G | Bridgestone data book 2023 (9 models) |
| 285/75R24.5 | 40.8–42.2" | 10.7–11.4" | 8.27" (calc.) | n/a | 492–509 | G | Bridgestone data book 2023 (8 models) |
| 11R22.5 | 40.6–42.4" | 10.8–11.6" | no aspect ratio | n/a | 490–512 | G | Bridgestone data book 2023 (10 models) |
| 445/50R22.5 | 39.2–39.9" | 17.7–19.4" | 8.74" (calc.) | n/a | 524–533 | L | Bridgestone data book 2023 (2 models) |
| 225/70R19.5 | 32.2–32.5" | 8.5–8.7" | 6.19" (calc.) | n/a | 639–644 | G | Bridgestone data book 2023 (3 models) |
| 35×12.50R17 | 35.0" | 12.5" | 8.5" | 109.9" | 577 | n/a | Flotation size, 35 in nominal height |
| 37×12.50R17 | 37.0" | 12.5" | 9.5" | 116.2" | 546 | n/a | Flotation size, 37 in nominal height (Raptor 37 Package) |
| 315/70R17 | 34.4" | 12.4" | 8.63" | 108.0" | 587 | n/a | Closest metric size to 35x12.50R17 (calculated); Ford lists LT315/70R17 for the F-150 Raptor |
Calculated values come from the size code. Actual diameter varies by tire model, so check the tire maker's listed dimensions and your vehicle placard and owner's manual before buying.
How Truck Tire Diameter Is Calculated for All Three Formats
Metric Format (295/75R22.5)
Metric (295/75R22.5): Sidewall Height = (295 mm × 0.75) ÷ 25.4 = 8.72 in Outer Diameter = 22.5 + (2 × 8.72) = 39.9 in (Bridgestone lists 39.5–41.0 in across models) Circumference = π × 39.9 = 125.3 in Revs/Mile = 63,360 ÷ 125.3 = 505
Legacy Numeric Format (11R22.5)
Legacy Numeric (11R22.5): No aspect ratio in the code, so the calculator estimates: Sidewall Height ≈ 11 in × 0.86 = 9.46 in (estimate matched to the data book) Outer Diameter ≈ 22.5 + (2 × 9.46) = 41.4 in (Bridgestone lists 40.6–42.4 in) Revs/Mile ≈ 63,360 ÷ (π × 41.4) = 487 (Bridgestone lists 490–512)
Flotation / Inch Format (35×12.50R17) & Gear Ratio
Flotation (35×12.50R17): Outer Diameter = 35.0 in (stated directly) Circumference = π × 35.0 = 109.9 in Revs/Mile = 63,360 ÷ 109.9 = 577 Gear Ratio Recalibration: New Ratio = Stock Ratio × (New OD ÷ Stock OD) Example: 3.55 × (35.0 ÷ 31.6) = 3.55 × 1.108 = 3.93 (ratio that restores the stock effective ratio)
- Larger OD → lower effective gear ratio → higher cruise RPM for the same speed. Manufacturers publish no re-gear advice; the calculator shows the effective ratio.
- Larger OD → speedometer reads low → you are going faster than displayed. Ask a dealer about speedometer calibration.
- Higher load index / load range → more weight capacity and higher recommended PSI. Never exceed load range rated for your axle GAWR.
Pickup Truck Tire Sizes From Owner's Manuals
Manufacturers publish the tire sizes their trucks are listed with, not lift heights, maximum tire sizes or clearance limits, so this table lists only sizes that appear in the documents. Ford's manual warns to use the exact original brand, size and construction, and says other combinations, even with identical size ratings, may result in insufficient running clearances, tire rubbing and eventual puncture. Overall diameters are calculated.
| Truck (document) | Tire sizes listed | Calculated overall diameter (in) |
|---|---|---|
| Ford F-150 (2026 specifications) | 245/70R17, 265/70R17, 265/60R18, 275/65R18, 275/70R18, 275/60R20, 275/50R22, LT315/70R17, 37x12.5R17 | 30.50, 31.61, 30.52, 32.07, 33.16, 32.99, 32.83, 34.36, 37.00 (nominal) |
| RAM 1500 (2025 manual) | 275/65R18, 275/55R20 | 32.07, 31.91 |
| RAM 2500 (2025 manual) | LT245/70R17E, LT285/70R17D, LT275/70R18E, LT285/60R20E | 30.50, 32.71, 33.16, 33.46 |
| GMC Sierra 1500 (2025 manual, tire chain section) | 275/50R22, 275/60R20, LT265/60R20, LT265/70R17, LT275/65R18, LT275/70R18 | 32.83, 32.99, 32.52, 31.61, 32.07, 33.16 |
| GMC Sierra 2500 HD / 3500 HD (2025 manual) | LT235/80R17, LT245/75R17, LT265/70R17, LT275/70R18, LT275/65R20, LT305/70R18E | 31.80, 31.47, 31.61, 33.16, 34.07, 34.81 |
| Toyota Tacoma (2025 manual) | 245/70R17, 265/70R17, 265/65R18 | 30.50, 31.61, 31.56 |
| Jeep Wrangler JL (2025 manual) / Gladiator (2022) | 245/75R17, 255/70R18, LT285/70R17C, LT315/70R17C, 275/55R20 | 31.47, 32.06, 32.71, 34.36, 31.91 |
Trim breakdowns, axle ratios and wheel offsets are not in these documents. Truck-specific pages cover the published detail, such as the F-150 tire size calculator.
Flotation to Metric Tire Size Conversion Chart
Closest metric size for common flotation sizes. The metric diameter is calculated as rim diameter plus twice the width times the aspect ratio, and the difference is measured against the flotation nominal diameter.
| Flotation size | Closest metric size | Metric diameter (calculated) | Nominal width | Difference |
|---|---|---|---|---|
| 31×10.50R15 | 265/75R15 | 30.6" | 10.5" | -1.1% |
| 33×12.50R15 | 315/75R15 | 33.6" | 12.5" | +1.8% |
| 33×12.50R17 | 295/70R17 | 33.3" | 12.5" | +0.8% |
| 35×12.50R17 | 315/70R17 | 34.4" | 12.5" | -1.8% |
| 35×12.50R18 | 305/70R18 | 34.8" | 12.5" | -0.5% |
| 37×12.50R17 | 315/80R17 | 36.8" | 12.5" | -0.4% |
| 37×13.50R17 | 345/75R17 | 37.4" | 13.5" | +1.0% |
| 40×13.50R17 | 355/80R17 | 39.4" | 13.5" | -1.6% |
How to Use This Truck Tire Size Calculator
- 1Enter your stock tire size: In the Size Difference tab, type your current tire size in any format: metric (295/75R22.5), numeric (11R22.5) or flotation (35×12.50R17). LT prefixes such as LT265/70R17 are accepted.
- 2Enter your proposed new size: Type the new tire size you are considering in the New / Proposed field. You can mix formats, for example a flotation size against a metric size.
- 3Add your stock gear ratio (optional): Enter your current axle gear ratio (for example 3.55 or 3.73). The calculator shows the effective ratio after the tire change and the ratio that would restore the stock effective ratio.
- 4Use a quick preset: Click a preset swap for F-150, Silverado, Ram, Tacoma, Jeep or semi truck sizes to fill both fields, then press Calculate.
- 5Read the results: Review the diameter change, the speedometer correction table (25 to 80 mph), the gear ratio result if you entered an axle ratio, and the sidewall height, circumference and revolutions per mile of both tires.
- 6Check the load index: Use the Load Index tab to convert a load index from the sidewall to pounds and kilograms per tire, and to total capacity for several tires. The semi tire chart and reference tables below list sizes, diameters and load ranges.
How to Read a Truck Tire Size
| Format | Example | What the numbers mean | Notes |
|---|---|---|---|
| Metric | 295/75R22.5 | 295 = width (mm), 75 = aspect ratio (%), R = radial, 22.5 = rim diameter (in) | Overall diameter = rim + 2 × (width × aspect ratio) |
| Numeric (legacy) | 11R22.5 | 11 = width (in), R = radial, 22.5 = rim diameter (in) | No aspect ratio, so the diameter comes from the tire maker's data book |
| Flotation | 35×12.50R17 | 35 = overall diameter (in), 12.50 = width (in), R = radial, 17 = rim diameter (in) | Overall diameter is stated in the size |
| Wide-base single | 445/50R22.5 | 445 = width (mm), 50 = aspect ratio (%) | Single tire in place of a dual pair, listed in tire-maker data books |
On a commercial tire a pair such as 144/141L gives the load index for single and dual use, followed by the speed symbol. In Bridgestone's data book L is 75 mph (120 km/h) and M is 81 mph (130 km/h).
Load Range and Load Index Reference
Bridgestone's data book says there is no industry-wide definition of ply rating; truck tires are marked with a ply rating and an equivalent load range to identify the load and inflation limits of that tire. Maximum inflation depends on the tire size: 295/75R22.5 load range G is rated at 110 psi, 11R22.5 load range G at 105 psi and 315/80R22.5 load range L at 130 psi. The load range and ply rating converter lists maximum pressures and loads for more example sizes.
| Load range | Ply rating |
|---|---|
| A | 2-ply |
| B | 4-ply |
| C | 6-ply |
| D | 8-ply |
| E | 10-ply |
| F | 12-ply |
| G | 14-ply |
| H | 16-ply |
| J | 18-ply |
| L | 20-ply |
| M | 22-ply |
| Load index | Pounds per tire |
|---|---|
| 125 | 3,640 lb |
| 133 | 4,540 lb |
| 136 | 4,940 lb |
| 140 | 5,510 lb |
| 141 | 5,675 lb |
| 144 | 6,175 lb |
| 146 | 6,610 lb |
| 149 | 7,160 lb |
| 150 | 7,390 lb |
| 160 | 9,920 lb |
| 161 | 10,200 lb |
| 166 | 11,700 lb |
Truck Tire Rules From Manufacturer Manuals
Match Diameter on Tandem Axles
Michelin's Truck Tire Service Manual says tires mounted in dual must be matched to within ¼ inch in diameter (or ¾ inch in circumference), and that tandem drive axles without an inter-axle differential, or with it locked out, need closely matched tires.
Gear Ratio With Bigger Tires
A taller tire lowers the effective gear ratio by the same percentage as the diameter change. Use the Size Difference tab with your own axle ratio to see the calculated effective ratio and the ratio that would restore stock. Manufacturers publish no re-gear advice, so ask a dealer which ratios exist for your truck. The effective gear ratio calculator shows the same arithmetic on its own page.
Load Range and Axle Weight Rating
Your vehicle's placard and owner's manual specify the tire size, load index and inflation pressure. Use tires that meet them, and check the axle total against your axle weight rating. The load range to ply rating converter and the load index chart list the figures.
Flotation vs. Metric Sizes
35×12.50R17 is nominally 35 in tall and 315/70R17 calculates to 34.4 in. The flotation to metric chart above lists more pairs. Overall diameter varies by tire model, so check the tire maker's listed diameter when it matters. A longer list of inch sizes in metric is on the flotation to metric size chart.
Check Pressure Cold
Michelin's Truck Tire Service Manual says to check all tires when cold, at least 3 hours after the vehicle has stopped, and never to bleed pressure from hot tires.
LT vs. P-Metric on Heavy-Duty Pickups
Use the tire type and size your owner's manual and placard specify. Ford, RAM and GMC manuals list LT sizes for their heavy-duty trucks (see the pickup size table); check a dealer before changing tire type.