4x100 Bolt Pattern
4x100 means 4 lugs on a 100.0 mm bolt circle, which is 3.94 inches, so the same pattern is written 4x3.94. Check a measurement against it below.
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4x100 dimensions
| Measurement | mm | inches |
|---|---|---|
| Bolt circle (PCD) | 100.0 mm | 3.937 in |
| Neighboring studs, center to center | 70.7 mm | 2.784 in |
Measure from the center of one stud to the center of the stud directly across.
Every way to write it
| Unit | Value |
|---|---|
| Millimeters | 100.0 |
| Inches | 3.937 |
| Centimeters | 10.00 |
| Neighbor studs (mm) | 70.7 |
To convert, divide the millimeter figure by 25.4: 100.0 ÷ 25.4 = 3.937 inches. Going the other way, multiply inches by 25.4.
Measuring with a tape
Center to center straight across reads the bolt circle directly: 100.0 mm (3.94 in). Neighboring studs are 70.7 mm (2.78 in) apart center to center, which is a useful second check.
Other 4-lug patterns compared
| Pattern | Bolt circle | Difference | In inches |
|---|---|---|---|
| 4x108 | 108.0 mm | +8.0 mm | 0.315 in |
| 4x114.3 | 114.3 mm | +14.3 mm | 0.563 in |
Wheels must match the bolt circle exactly; an adapter is the only way to mount a different pattern.
What your tape should read
For 4, 6 and 8 lugs the first column is center to center straight across; for 5 lugs it is center to center across one skipped stud. The second column is the distance between neighboring studs, a handy cross-check on any pattern.
| Pattern | Main reading | Neighbor studs |
|---|---|---|
| 4x100 | 100.0 mm (3.94 in) | 70.7 mm (2.78 in) |
| 4x108 | 108.0 mm (4.25 in) | 76.4 mm (3.01 in) |
| 4x114.3 | 114.3 mm (4.50 in) | 80.8 mm (3.18 in) |
| 5x100 | 95.1 mm (3.74 in) | 58.8 mm (2.31 in) |
| 5x108 | 102.7 mm (4.04 in) | 63.5 mm (2.50 in) |
| 5x112 | 106.5 mm (4.19 in) | 65.8 mm (2.59 in) |
| 5x114.3 | 108.7 mm (4.28 in) | 67.2 mm (2.65 in) |
| 5x120 | 114.1 mm (4.49 in) | 70.5 mm (2.78 in) |
| 5x127 | 120.8 mm (4.76 in) | 74.6 mm (2.94 in) |
| 5x135 | 128.4 mm (5.05 in) | 79.4 mm (3.12 in) |
| 5x139.7 | 132.9 mm (5.23 in) | 82.1 mm (3.23 in) |
| 6x114.3 | 114.3 mm (4.50 in) | 57.1 mm (2.25 in) |
| 6x135 | 135.0 mm (5.31 in) | 67.5 mm (2.66 in) |
| 6x139.7 | 139.7 mm (5.50 in) | 69.8 mm (2.75 in) |
| 8x165.1 | 165.1 mm (6.50 in) | 63.2 mm (2.49 in) |
| 8x170 | 170.0 mm (6.69 in) | 65.1 mm (2.56 in) |
Computed from the bolt circle: straight across = PCD; skip one (5 lug) = PCD × sin 72°; neighbors = PCD × sin(180° ÷ lugs).
Before you buy wheels
- The stud count and bolt circle must match exactly; a wheel drilled a millimeter or two off will not seat properly on every stud.
- Check the center bore and the lug nut or bolt seat type along with the pattern.
- When the wheel lists its pattern, compare it with the number stamped on your current wheel rather than a tape reading.
Common questions
Is 4x100 the same as 4x3.94?
Yes. 100.0 mm ÷ 25.4 = 3.937 in.
What is 4x100 in inches?
4x3.94.
How far apart are neighboring studs on 4x100?
70.7 mm center to center.
Related calculators
Sources
- https://tiregrades.com/tire-anatomy/wheels/how-to-measure-bolt-pattern
- https://drivenproducts.com/blogs/wheel-and-wheel-accessory-terminology/wheel-bolt-patterns-and-bolt-circles
- https://www.cokertire.com/blog/measuring-wheel-bolt-pattern/