How to Measure a Bolt Pattern: 4, 5, 6 & 8 Lug Wheels
A wheel’s bolt pattern tells you how many mounting holes or studs it uses and the diameter of the circle formed by those mounting points. Knowing how to measure a bolt pattern is useful when identifying a wheel, checking vehicle specifications, or comparing replacement wheels.
The basic process is straightforward for 4-, 6-, and 8-lug patterns because there is a mounting point directly opposite another. Five-lug patterns require a different measurement method and should be confirmed carefully because several common patterns have very similar dimensions.
Bolt Pattern Example: What Does 5×114.3 Mean?
A bolt pattern written as 5×114.3 means:
- 5 = five wheel mounting holes or studs
- 114.3 = the pitch circle diameter, or PCD, measured in millimeters
The same pattern may also be described as approximately 5×4.5 inches.
What Is a Wheel Bolt Pattern?
A wheel bolt pattern describes the number of mounting points and the diameter of the imaginary circle that passes through their centers. This circle is commonly called the pitch circle diameter (PCD).
For example:
- 4×100 = 4 mounting points on a 100 mm circle
- 5×114.3 = 5 mounting points on a 114.3 mm circle
- 6×139.7 = 6 mounting points on a 139.7 mm circle
- 8×165.1 = 8 mounting points on a 165.1 mm circle
The bolt pattern must match the vehicle’s wheel mounting pattern. However, matching the bolt pattern alone does not guarantee that a wheel will fit correctly.
What You Need to Measure a Bolt Pattern
For a basic measurement, you can use:
- a ruler with millimeter markings
- a tape measure
- digital or vernier calipers for more precise measurements
- a dedicated bolt-pattern or PCD gauge for the most reliable identification
A bolt-pattern gauge is especially useful for 5-lug wheels because nearby patterns such as 5×112, 5×114.3, and 5×115 can be difficult to distinguish with a rough manual measurement.
How to Measure a 4-Lug Bolt Pattern
A 4-lug pattern is one of the easiest to measure because each mounting hole has another hole directly opposite it.
- Count the mounting holes to confirm that there are four.
- Choose any mounting hole.
- Find the hole directly opposite it.
- Measure from the center of the first hole to the center of the opposite hole.
- That measurement is the PCD.
For example, a center-to-center measurement of approximately 100 mm indicates a 4×100 bolt pattern.
How to Measure a 5-Lug Bolt Pattern
A 5-lug bolt pattern is more difficult because there is no mounting hole directly opposite another hole.
For a quick wheel measurement, one commonly used method is to measure from the far or back edge of one lug hole to the center of the lug hole two positions away.
- Confirm that the wheel has five mounting holes.
- Select one hole as your starting point.
- Skip the adjacent hole and locate the next hole.
- Measure from the far edge of the starting hole to the center of that second hole.
- Compare the result with known 5-lug bolt-pattern dimensions.
This manual method is useful for identifying a likely pattern, but it should be treated as an approximation. A bolt-pattern gauge or verified vehicle/wheel specification is better when exact identification is important.
Be Careful With Similar 5-Lug Patterns
Do not assume two patterns are interchangeable because their measurements look close. Patterns such as 5×112, 5×114.3, and 5×115 are different specifications.
When in doubt, confirm the exact vehicle specification or use a proper PCD gauge before installing the wheel.
How to Measure a 6-Lug Bolt Pattern
A 6-lug wheel can be measured using the same basic method as a 4-lug wheel because each hole has another mounting hole directly opposite it.
- Choose one mounting hole.
- Locate the hole directly across the wheel center.
- Measure from the center of one hole to the center of the opposite hole.
- The resulting measurement is the PCD.
For example, a measurement of approximately 139.7 mm indicates a 6×139.7 bolt pattern, which may also be expressed as approximately 6×5.5 inches.
How to Measure an 8-Lug Bolt Pattern
Eight-lug patterns are also measured directly across the center of the bolt circle.
- Choose one lug hole or stud.
- Find the mounting point directly opposite it.
- Measure from center to center.
- Use the result as the PCD measurement.
Because truck wheel fitment can involve high loads and several related specifications, always confirm the pattern and wheel specifications for the exact vehicle before installation.
Bolt Pattern Measurement by Lug Count
| Lug Count | Basic Measurement Method | Difficulty |
|---|---|---|
| 4 lug | Center of one hole to center of the directly opposite hole | Easy |
| 5 lug | Special measurement because there is no directly opposite hole | Needs extra care |
| 6 lug | Center of one hole to center of the directly opposite hole | Easy |
| 8 lug | Center of one hole to center of the directly opposite hole | Easy |
How to Read the Measurement
Once you know the lug count and PCD, combine the two values to identify the pattern.
For example:
Millimeters vs Inches in Bolt Patterns
Bolt patterns may be listed in millimeters or inches. In some cases, the same pattern has commonly used metric and inch names.
Examples include:
- 5×114.3 ≈ 5×4.5
- 5×127 = 5×5
- 6×139.7 ≈ 6×5.5
- 5×120.65 = 5×4.75
Use the exact specified PCD whenever possible rather than assuming that every rounded inch measurement represents a different metric pattern.
Common Bolt Pattern Measurement Mistakes
Measuring Edge to Edge on an Even-Lug Pattern
For 4-, 6-, and 8-lug patterns, the PCD measurement should be taken from the center of one mounting point to the center of the mounting point directly opposite it.
Treating a 5-Lug Pattern Like a 4-Lug Pattern
A 5-lug wheel does not have a hole directly opposite another hole, so the simple center-to-center method used for even-lug wheels cannot be applied in the same way.
Rounding Similar Patterns
A rough measurement can make two different bolt patterns appear identical. This is especially important with closely spaced 5-lug patterns.
Assuming Bolt Pattern Alone Means the Wheel Fits
Matching the PCD is necessary, but it is only one part of wheel fitment.
Does the Same Bolt Pattern Mean a Wheel Will Fit?
No. Two wheels can share the same bolt pattern and still be incompatible with a vehicle.
Other important specifications include:
- wheel diameter
- wheel width
- wheel offset
- backspacing
- center bore
- brake clearance
- suspension clearance
- load rating
- lug nut or wheel-bolt hardware
For a broader explanation of these measurements, see our Wheel Fitment & Wheel Specifications guide.
How to Find Your Vehicle’s Bolt Pattern Without Measuring
If the exact vehicle is known, checking a reliable vehicle-specific fitment source is generally better than relying on a manual measurement alone.
Use our Vehicle Tire & Wheel Fitment section to research available specifications by year, make, model, and trim as the FitmentCompass database expands.
You can also explore individual FitmentCompass bolt-pattern pages for measurements, equivalent notation, fitment considerations, and related information.
When Should You Use a Bolt Pattern Gauge?
A dedicated bolt-pattern gauge is useful when:
- the wheel or vehicle specification is unknown
- you are measuring a 5-lug pattern
- two possible patterns are very close together
- you are identifying an unmarked aftermarket wheel
- you need greater confidence than a tape-measure estimate can provide
For final installation decisions, a verified vehicle specification or accurate PCD measurement is preferable to guessing from an approximate measurement.
Research Wheel Fitment by Vehicle
Check tire and wheel fitment by year, make, model, and trim instead of relying on bolt pattern alone.
Frequently Asked Questions
How do you measure a wheel bolt pattern?
For an even-number lug pattern such as 4, 6, or 8 lugs, measure from the center of one mounting hole to the center of the hole directly opposite it. Five-lug patterns require a different method because no hole sits directly opposite another.
How do you measure a 5-lug bolt pattern?
A common quick method is to measure from the far edge of one lug hole to the center of the lug hole two positions away. Because several 5-lug patterns are very close in size, use a bolt-pattern gauge or verified vehicle specification when exact identification is required.
What does 5×114.3 mean?
5×114.3 means the wheel has five mounting holes positioned on an imaginary circle with a diameter of 114.3 millimeters. It is also commonly described as approximately 5×4.5 inches.
Is PCD the same as bolt pattern?
PCD means pitch circle diameter and refers specifically to the diameter of the imaginary circle through the mounting points. A complete bolt pattern combines the lug count with the PCD, such as 5×114.3.
Can two different vehicles have the same bolt pattern?
Yes. Many vehicles share a bolt pattern, but that does not mean their wheels are automatically interchangeable. Center bore, wheel width, diameter, offset, brake clearance, load capacity, and mounting hardware also matter.
Does matching the bolt pattern guarantee that a wheel will fit?
No. The bolt pattern must match, but correct wheel fitment also depends on center bore, wheel diameter and width, offset, backspacing, brake and suspension clearance, load rating, and appropriate mounting hardware.
Fitment note: A manual bolt-pattern measurement is useful for identification, but wheel compatibility should be confirmed using the exact vehicle and wheel specifications before installation. Matching the PCD alone does not establish complete wheel fitment.
