DIY Alignment Calculator

* Disclaimer: Always verify the calculated values before relying on the data for any practical application.

A =
toe ° =
B =
I =
J =
C =
toe ° =
D =
(Alignment Setup Diagram)
E =
toe ° =
F =
K =
G =
toe ° =
H =


Angle between chassis centerline and strings =

Track difference (positive if rear is wider than front) =

Total front toe:

Total rear toe:

Thrust angle of rear wheels =

Usage:
1) You will need to allow Javascript for this page to work as intended.
2) The blue lines represent the two strings. The strings must be parallel to each other, but they do not need to be parallel to the vehicle. The calculator can determine the vehicle's angle relative to the strings based on the data entered, and therefore provides the toe angles relative to the vehicle.
3) The same unit of measurement must be used for all data entered. The calculator doesn't care what unit is used, since the calculated angles are in degrees.
4) Wheel to string measurements are made perpendicular to the string.
5) The calculator does not assume that the front and rear track are the same. It determines the difference in the front and rear track based on the measurements entered. The only assumption is that the left and right tires are evenly spaced around the vehicle's centerline and that the cross camber is near zero. This also means that if the measurements are not made accurately, changes on a single wheel could result in a very minor calculated change on the toe angles of the other wheels.
6) Because the strings do not need to be parallel to the vehicle, a wheelbase measurement is needed to complete the calculations. Be sure to use the same unit of measurement for the wheelbase.
7) I and J should be the diameter of the wheel locations at which the distances from the lines are measured (ie. 17" wheels do not have 17" diameter at the edge of the wheel where you measure!).

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