FITMENTNORTH
Validation build 01

Wheel & tyre geometry, made visible

Know what fits.
See how it sits.

Compare your current setup with the wheels you want. Get the position, clearance and speedometer changes in millimetres—not forum guesswork.

Compare my setup No account. Measurements stay on your device.
  • POSWheel position
  • DIARolling diameter
  • SPDSpeed difference

Manual comparison

Compare the setup you have with the one you want.

Start with your vehicle to load its factory tyre size, then enter wheel width and offset for the setup you want to compare.

Find your factory tyre sizeChoose year, make, model and trim. Wheel width and offset stay manual.
Live vehicle data

Connecting to vehicle data…

Current setup
Current wheel and tyre specifications
Proposed setup
Proposed wheel and tyre specifications
Measured change Manual geometry

The new setup sits 23 mm further out.

You gain a small amount of inner clearance and keep the rolling diameter close to the current setup.

Suspension
Fender
Wheel position comparison Current and proposed wheel widths positioned relative to the hub mounting face. HUB FACE CURRENT PROPOSED
Outer position
+22.7 mm
further toward fender
Inner clearance
-2.7 mm
slightly less space
Diameter change
-0.5%
close to current diameter
At indicated 100
99.5
estimated actual speed
Geometry is not a fitment guarantee

This calculation cannot see brake-caliper shape, suspension movement, fender modifications, hub bore, load rating or bolt-seat type. Confirm the exact vehicle with a qualified retailer or installer.

What would you do next?This private test stores your choice only on this device.

Useful numbers. Honest boundaries.

Wheel width and offset tell us how the rim moves around the mounting face. Tyre dimensions tell us how rolling diameter changes. Neither calculation can inspect the physical car, so the final installation still needs a vehicle-specific check.

  1. MeasureRead the stamped wheel and tyre sizes.
  2. CompareSee movement in millimetres, not jargon.
  3. VerifyConfirm the vehicle before ordering.

How the manual comparison works

Wheel position

Declared wheel width is converted to millimetres. Half the width is positioned on either side of the mounting face, then adjusted by the offset. The result shows relative movement only; it does not know the car's available space.

Tyre diameter and speed

Overall diameter is the rim diameter plus twice the sidewall height. The speed estimate assumes the current tyre diameter matches the vehicle's calibration and does not account for tread wear or manufacturer variation.

What vehicle lookup can and cannot fill

The lookup loads factory tyre width, aspect ratio and rim diameter from licensed vehicle data. Wheel width, offset, brake clearance and body clearance still need to be read from the wheel or confirmed by a qualified retailer or installer.