Alternate Tire Size Finder
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
OEM 265/70R17 is 803 mm (31.61 in) overall. Showing calculated reference sizes within the tolerance — availability varies by market.
14 alternate sizes
| Size | Diameter | Δ dia | Clearance | Δ width | Revs/km | Risk |
|---|---|---|---|---|---|---|
| 285/65R17 | 802 mm | -0.1% | -0.3 mm | +20 mm | 397 | Low |
| 245/75R17 | 799 mm | -0.4% | -1.8 mm | -20 mm | 398 | Low |
| 305/60R17 | 798 mm | -0.6% | -2.5 mm | +40 mm | 399 | Low |
| 235/80R17 | 808 mm | +0.6% | +2.5 mm | -30 mm | 394 | Low |
| 315/60R17 | 810 mm | +0.9% | +3.5 mm | +50 mm | 393 | Low |
| 225/80R17 | 792 mm | -1.4% | -5.5 mm | -40 mm | 402 | Check |
| 255/75R17 | 814 mm | +1.4% | +5.8 mm | -10 mm | 391 | Check |
| 295/65R17 | 815 mm | +1.6% | +6.3 mm | +30 mm | 390 | Check |
| 275/65R17 | 789 mm | -1.7% | -6.8 mm | +10 mm | 403 | Check |
| 255/70R17 | 789 mm | -1.7% | -7.0 mm | -10 mm | 404 | Check |
| 275/70R17 | 817 mm | +1.7% | +7.0 mm | +10 mm | 390 | Check |
| 295/60R17 | 786 mm | -2.1% | -8.5 mm | +30 mm | 405 | Check |
| 235/75R17 | 784 mm | -2.3% | -9.3 mm | -30 mm | 406 | Check |
| 245/80R17 | 824 mm | +2.6% | +10.5 mm | -20 mm | 386 | Check |
Estimates only — check before you fit
These results are calculated from tyre-size geometry and the values you enter. Real tyre dimensions vary by brand, model, load, pressure and wear. Always check the vehicle placard, tyre manufacturer data, local road rules, and guard / brake / suspension clearance, and get professional fitment advice before changing tyre or wheel sizes. A listed size is a calculated reference and may not be manufactured or suitable for your vehicle.
How to use this calculator
- Enter your current (OEM) tyre size in any format.
- Pick a diameter tolerance (±1–5%) and whether to keep the same rim.
- Read the ranked alternatives — each with overall diameter, diameter %, clearance change, width change, revs/km and a fitment-risk badge.
How it works
The tool computes your OEM overall diameter, then searches a generated library of common tyre sizes for those whose diameter is within your chosen tolerance, ranked closest-first.
These are calculated reference sizes (original Zerdly data, not an availability database) — a listed size may not be manufactured for your market or suit your vehicle.
Worked example
265/70R17 within ±3%. Returns same-rim sizes whose overall diameter sits within about ±24 mm of the OEM ~803 mm, sorted by how close they are.
Frequently asked questions
What is plus-sizing?
Fitting a larger-diameter rim with a lower-profile tyre to keep about the same overall diameter. Allow other rims and a tight tolerance to see plus-size options.
Are all these sizes available to buy?
Not necessarily. They're calculated references generated from common width/aspect/rim combinations. Always confirm a size is actually made and suitable before buying.
How much diameter change is OK?
Many people aim to stay within a few percent of the original diameter to limit speedo error and fitment issues, but the right limit depends on the vehicle and local rules.
Are these results safe to fit?
They're geometry estimates only. Real tyres vary by brand, load, pressure and wear. Always check the vehicle placard, manufacturer data, local road rules and guard/brake/suspension clearance, and get professional fitment advice before changing tyre or wheel sizes.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.