A tire's total height (overall diameter) is calculated as: Rim Diameter + 2 × Sidewall Height, where Sidewall Height = (Section Width mm × Aspect Ratio ÷ 100) ÷ 25.4 inches. For example, a 265/70R17 tire has a sidewall of (265 × 0.70) ÷ 25.4 = 7.30 inches, giving a total height of 17 + 2 × 7.30 = 31.61 inches. The ±3% rule means a safe replacement tire must have a total height within 3% of your OEM size to maintain speedometer accuracy and ABS calibration.
Tire Height Calculator
Calculate total tire height in inches or mm — from any P-metric code, inch-direct entry, or by comparing two sizes side-by-side. Five modes: metric decode, inches direct, comparison, wheel+tire total, and reverse height lookup.
QUICK EXAMPLE
A Toyota Tacoma leaves the factory on 265/70R17 tires — a total height of 31.61 inches — which has become one of the most common off-road starting points in North America. A popular upgrade path moves to 285/75R17, raising total height to 33.83 inches, a +6.8% increase well beyond the passenger-car ±3% guideline, but acceptable on this body-on-frame truck with a 2-inch leveling kit. Run the same swap on a car-based crossover and the ABS wheel-speed sensors immediately log fault codes. Use the comparison tab below to verify the exact height delta and speedometer correction before purchasing any tire.
Tire Height Calculator — Metric Size (P-Metric)
Common sizes — quick load:
Pre-Computed Heights — 12 Popular Metric Sizes
| Size | Height (in) | Height (mm) | Sidewall (in) | Circumference (in) | Revs/Mile | Category |
|---|---|---|---|---|---|---|
| 24.47″ | 621.5 | 4.73″ | 76.87″ | 824 | Economy sedan | |
| 24.98″ | 634.5 | 4.99″ | 78.48″ | 807 | Compact | |
| 24.88″ | 631.9 | 4.44″ | 78.16″ | 811 | Midsize sedan | |
| 26.16″ | 664.4 | 5.08″ | 82.18″ | 771 | Family car | |
| 24.97″ | 634.3 | 3.99″ | 78.45″ | 808 | Sport sedan | |
| 28.52″ | 724.3 | 5.76″ | 89.58″ | 707 | Crossover / SUV | |
| 28.18″ | 715.7 | 5.09″ | 88.52″ | 716 | Mid-size SUV | |
| 26.68″ | 677.7 | 4.34″ | 83.82″ | 756 | Performance | |
| 31.61″ | 802.8 | 7.30″ | 99.29″ | 638 | Truck / light off-road | |
| 32.07″ | 814.7 | 7.04″ | 100.77″ | 629 | Half-ton truck | |
| 32.83″ | 833.9 | 8.42″ | 103.14″ | 614 | Jeep / off-road | |
| 34.36″ | 872.8 | 8.68″ | 107.95″ | 587 | Lifted truck |
Click any size to load it into the calculator above.
How to Use This Calculator
- 1Tab 1 — Metric Size: Type your P-metric tire code (e.g. 225/65R17) or click a preset. Click "Calculate Height" to see total height, sidewall, circumference, and revs/mile in both inches and mm.
- 2Tab 2 — Inches Direct: Enter the rim diameter and the tire sidewall height in inches. Use this for floatation sizes (35×12.5R17), trailer tires, or any tire where you have a physical measurement. The mm↔inch reference table is expandable below.
- 3Tab 3 — Compare Two: Enter Size A (your current/OEM tire) and Size B (your proposed new tire). The calculator outputs height delta, safety badge (ideal/acceptable/caution/danger), a visual SVG comparison, and a per-speed speedometer correction table.
- 4Tab 4 — Wheel + Tire Total: Enter wheel rim diameter and one sidewall height in inches to see the complete assembled height — useful for custom builds, trailers, and ground-clearance planning.
- 5Tab 5 — Find by Height: Enter a target height in inches and a rim size. The calculator scans over 1,000 standard metric combinations and returns every size within ±2%, sorted by closest match.
- 6Global: Use the Inches/Metric toggle (top right) to switch all displayed results between imperial and metric. Click "Copy Results" to copy the current calculation to your clipboard.
Tire Height Reference Table — 12 Popular Sizes
| Size | Height (in) | Height (mm) | Sidewall (in) | Circumference (in) | Revs / Mile | Typical Vehicle |
|---|---|---|---|---|---|---|
| 185/65R15 | 24.47″ | 621.6 | 4.74″ | 76.89″ | 824 | Economy sedan (Corolla, Civic) |
| 195/65R15 | 25.00″ | 635.0 | 5.00″ | 78.54″ | 806 | Compact (Golf, Focus) |
| 205/55R16 | 24.88″ | 631.9 | 4.44″ | 78.15″ | 810 | Midsize sedan (Camry, Accord) |
| 225/45R17 | 24.96″ | 634.0 | 3.98″ | 78.41″ | 808 | Sport sedan / coupe |
| 225/65R17 | 28.44″ | 722.4 | 5.72″ | 89.32″ | 709 | Crossover / SUV (RAV4, CR-V) |
| 245/65R17 | 29.53″ | 750.0 | 6.27″ | 92.74″ | 683 | Mid-size SUV (Highlander, Pilot) |
| 265/70R17 | 31.61″ | 802.9 | 7.30″ | 99.29″ | 638 | Truck / Jeep (Tacoma stock) |
| 275/65R18 | 32.07″ | 814.6 | 7.04″ | 100.73″ | 629 | Half-ton truck (F-150, Silverado) |
| 285/75R16 | 32.83″ | 834.0 | 8.41″ | 103.13″ | 614 | Jeep Wrangler / off-road |
| 305/55R20 | 32.01″ | 813.1 | 6.59″ | 100.54″ | 630 | Full-size truck (Ram 1500 stock) |
| 315/70R17 | 34.36″ | 872.7 | 8.68″ | 107.91″ | 587 | Lifted truck / heavy off-road |
| 35×12.5R17 | 34.83″ | 884.7 | 8.90″ | 109.40″ | 579 | 35″ floatation (common lift size) |
Heights are calculated from ISO/SAE P-metric standard formulas. The 35×12.5R17 floatation size uses nominal inch dimensions. All values assume standard inflation pressure — actual dimensions may vary ±1–2% by manufacturer.
Inch-to-Metric Tire Height Quick Reference
| Target Height | Rim | Closest Metric Size | Actual Height | Δ from Target | Application |
|---|---|---|---|---|---|
| 26″ | 17″ | 215/65R17 | 27.48″ | +1.48″ | Stock SUV / crossover |
| 28″ | 17″ | 225/65R17 | 28.52″ | +0.52″ | Crossover upgrade |
| 29″ | 17″ | 235/65R17 | 29.00″ | +0.00″ | Compact truck |
| 30″ | 17″ | 245/70R17 | 30.47″ | +0.47″ | Full-size car / minivan |
| 31″ | 17″ | 265/70R17 | 31.61″ | +0.61″ | Light truck (Tacoma, Frontier) |
| 33″ | 17″ | 285/75R17 | 32.83″ | -0.17″ | Mild off-road (Jeep JK) |
| 33″ | 20″ | 275/65R20 | 33.06″ | +0.06″ | Modern truck 20″ wheel |
| 35″ | 17″ | 315/70R17 | 34.36″ | -0.64″ | Heavy off-road (TRD Pro) |
| 35″ | 20″ | 295/70R20 | 34.26″ | -0.74″ | Lifted truck 20″ wheel |
| 37″ | 17″ | 355/70R17 | 37.14″ | +0.14″ | Extreme off-road |
Use the Find by Height tab in the calculator above for a full scan — this table shows the single closest match per target; the tab returns all sizes within ±2%.
Tire Height Formulas — Complete Reference
Tire Height Formulas — Complete Reference
1. TOTAL HEIGHT FROM P-METRIC CODE (e.g. 265/70R17)
Step 1 — Sidewall Height (mm):
Sidewall_mm = Section Width × (Aspect Ratio ÷ 100)
= 265 × 0.70 = 185.5 mm
Step 2 — Sidewall Height (inches):
Sidewall_in = 185.5 ÷ 25.4 = 7.303 in
Step 3 — Total Height (Overall Diameter):
Total_Height = Rim_Diameter + 2 × Sidewall_in
= 17 + 2 × 7.303 = 31.61 in (802.9 mm)
2. TOTAL HEIGHT — INCH-DIRECT METHOD
Total_Height = Rim_Diameter + 2 × Sidewall_Height
Example — 35×12.5R17:
Total_Height = 17 + 2 × 8.875 = 34.75 in
3. CIRCUMFERENCE
C = π × Total_Height
C = 3.14159 × 31.61 = 99.29 in (2.522 m)
4. REVOLUTIONS PER MILE
Rev/Mile = 63,360 ÷ Circumference_in
= 63,360 ÷ 99.29 = 638 rev/mi
5. REVOLUTIONS PER KM
Rev/km = 39,370 ÷ Circumference_in
= 39,370 ÷ 99.29 = 396 rev/km
6. HEIGHT DIFFERENCE % (COMPARISON)
Δ% = ((New_Height − OEM_Height) ÷ OEM_Height) × 100
Example — 285/75R16 vs 265/70R16:
= ((32.83 − 30.55) ÷ 30.55) × 100 = +7.5%
7. SPEEDOMETER CORRECTION
True_Speed = Indicated_Speed × (New_Height ÷ OEM_Height)
If New > OEM → speedometer reads LOW (true speed is higher).
If New < OEM → speedometer reads HIGH (true speed is lower).
8. SAFE REPLACEMENT WINDOW (±3% RULE)
Safe_Max = OEM_Height × 1.03
Safe_Min = OEM_Height × 0.97
AWD vehicles: tighten to ±1% per most manufacturer specs.
9. GROUND CLEARANCE AT AXLE
Axle_Height = Total_Height ÷ 2 (the tire radius)
Every +2 in of total height = +1 in ground clearance at the axle center.P-Metric decoding — The three numbers in a P-metric tire code (e.g. 265/70R17) encode everything needed to calculate height. The first number is section width in millimetres; the second is the aspect ratio — sidewall height as a percentage of width; the third is the rim diameter in inches. The inconsistent unit system (mm width, % aspect ratio, inch rim) is a historical accident from the 1960s metrication of tire standards, but the formula is straightforward once you know the conversion factor of 25.4 mm per inch.
Tire height vs tire diameter— Both terms describe identical measurements: the outer diameter of a mounted, inflated tire from contact patch to the diametrically opposite point on the tread. Engineers and tire manufacturers use “overall diameter”; enthusiasts and off-road communities use “height”. You will encounter both in spec sheets — they are always the same number.
The ±3% safety rule— Tire-size change guides consistently cite ±3% overall diameter as the safe passenger-vehicle limit for maintaining ABS calibration, speedometer accuracy, and transmission shift-point integrity. For AWD and 4WD vehicles, most manufacturers reduce this to ±1% because continuous torque transfer between axles amplifies the mechanical stress from any circumference mismatch. The Compare tab in this calculator flags changes at four thresholds: ideal (<1%), acceptable (1–3%), caution (3–5%), and danger (>5%).
Aspect ratio and total height — A common misconception is that the aspect ratio alone determines tire height. In fact, two tires with the same aspect ratio can have very different heights if their widths differ. A 225/65R17 (5.76 in sidewall → 28.52 in total) and a 265/65R17 (6.78 in sidewall → 30.55 in total) both carry a 65-series aspect ratio but the wider tire is over two inches taller. Always calculate from the full three-number code, not the aspect ratio alone.