What size is my wheel nut?

There isn’t a single universal wheel nut size; the correct size depends on your vehicle’s wheel studs and lug nut type. To be sure, consult your owner’s manual, check the wheel or hub specifications, or measure the components with appropriate tools and compare to manufacturer specs.

Understanding lug nut sizing and how to determine yours

Wheel nuts, or lug nuts, come in several variations that must match your wheel studs, seat type, and wrench size. Getting the right combination ensures safe mounting and proper torque. Here’s how to identify your exact lug nut size for your vehicle.

To identify the correct lug nut size for your wheels, follow these practical steps:

• Identify the wheel stud diameter and thread pitch by checking the vehicle’s documentation or measuring the stud with calipers and a thread gauge.


• Check the lug nut seat type to match the wheel’s lug holes (most modern cars use a 60-degree conical seat; some wheels use ball or flat seats).


• Measure the lug nut width across flats (AF) to determine the wrench or socket size needed, and note the appropriate nut length if you’re replacing with a different style.


• Consult the vehicle’s owner’s manual, the wheel or hub manufacturer’s specifications, or a trusted parts retailer for the exact lug nut specification for your exact model and trim.

Using these steps helps ensure you select the correct size and seating. If you’re unsure, seek professional help or bring a sample nut to a parts store for matching.

Common lug nut sizes you may encounter

Here is a quick reference of sizes you’re likely to see on modern vehicles. Keep in mind that exact specs can vary by model, trim, and aftermarket wheels, so always verify before purchase or installation.

• Metric: M12 x 1.5 — the most common on modern passenger cars with 12 mm studs (often 60-degree conical seat).


• Metric: M12 x 1.25 — found on some models and earlier iterations; verify with your manual.


• Metric: M14 x 1.5 — used on larger wheels or certain trucks and SUVs; may require a larger wrench size.


• Imperial: 1/2"-20 UNC — encountered on some older American cars and trucks.


• Imperial: 9/16"-18 UNC — appears on a subset of heavy-duty or older applications.

Because wheel assemblies and aftermarket wheels can require different seats or accessory hardware, always confirm the exact specification for your vehicle and wheels with the manual or a knowledgeable retailer. Using the wrong size or seating can damage threads or compromise safety.

Seat types you may encounter

Most modern vehicles use a 60-degree conical seat, but some wheels employ ball seats or flat seats. The seat type must match the wheel’s lug hole design to ensure proper contact and torque distribution.

• 60-degree conical (most common on modern passenger cars)


• Ball seat


• Flat seat

When in doubt, verify seat type along with diameter and pitch, since a mismatch can prevent proper seating and even cause wheel vibration or damage over time.

What to do if you can’t determine the size

If you’re uncertain, take a measured sample to a parts retailer, consult your dealership, or use a VIN-based lookup service. Providing the exact year, make, model, and trim helps ensure you receive the correct lug nuts for your wheels.

Summary

Wheel nut size is model-specific and depends on stud diameter, thread pitch, and seat type. The most common modern configuration is metric M12 x 1.5 with a 60-degree conical seat, but variations exist across vehicles and aftermarket wheels. Always verify using the owner’s manual, manufacturer specifications, or a trusted parts supplier, and measure carefully when replacing parts. Correct sizing is essential for safe mounting and proper torque.

Is there a universal lug nut size?

No, you need to use the lug nut size specified for your vehicle for safe performance.

What can I do if I've lost my locking wheel nut?

If you've lost a locking wheel nut, you should first check common places it might have been stored and then contact a professional like a tire shop or dealership for removal. If that's not an option, you can try a DIY method of hammering a specialized or 12-point socket onto the nut to remove it. 
Step 1: Search for the key

• Look in common storage spots like the glove box, center console, under the spare tire, or in the trunk.
• Contact the last person or company who worked on your vehicle to see if they have it. 

Step 2: Seek professional removal

• Visit a tire shop or mechanic: These professionals have specialized tools and techniques to remove the nut without damaging your wheel. 
• Contact the dealership: They may be able to get a replacement key or have a procedure for removal. 

Step 3: Use a DIY removal method (if comfortable and the nut isn't a "spinning collar" type)

• Hammer on a socket: Hammer a 12-point socket that is slightly undersized over the locking nut. The socket's edges will bite into the nut, allowing you to use a breaker bar to twist it off. 
• Use a specialized removal tool: You can purchase a wheel lock removal kit that has a spiral groove for better grip than a standard socket. 
• Important: After removing the old locking nuts, replace them with standard lug nuts and ensure they are torqued correctly. 

This video demonstrates how to remove a locking lug nut using a specialized tool and a torque wrench: 54sChrisFixYouTube · Aug 13, 2023
Step 4: After removal

• Once the old locking wheel nut is removed, replace it with a standard wheel nut or purchase a new set to ensure the wheel is secure. 

How do I measure my lug nut size?

To measure a lug nut size, you need to find the diameter and thread pitch. The easiest way is to measure the outside diameter of the wheel stud with a caliper and then count the number of threads per inch (for SAE) or the distance between threads in millimeters (for metric). For a quick and accurate result, use a lug nut thread checker, as shown on this Amazon product page. 
Method 1: Using calipers and a thread gauge (most accurate) 
This video demonstrates how to measure wheel bolt patterns: 57sCountermanYouTube · Nov 15, 2024

1. Measure the stud diameter: Use a digital or dial caliper to measure the outside diameter of the wheel stud threads. This is the first number in the lug nut size (e.g., 12mm or 1/2"). 
2. Measure the thread pitch: 
   • For SAE (imperial) threads: Count the number of threads that fit within a one-inch section of the stud. For example, 20 threads per inch would be the second number. 
   • For Metric threads: Measure the distance in millimeters between two adjacent threads. This is the second number (e.g., 1.25mm). 
3. Combine the measurements: Combine the diameter and pitch to get the lug nut size, such as 12mm x 1.25 or 1/2"-20. 

Method 2: Using a lug nut thread checker

1. Use the tool: A lug nut thread checker is a tool with a series of male threads on one end and female holes on the other. 
2. Check the diameter: Insert the correct size wheel stud into the female holes until it fits snugly. The number etched on the hole corresponds to the diameter (e.g., 12mm or 1/2"). 
3. Check the pitch: Insert the correct size lug nut into the corresponding male thread on the tool. The number etched on the male thread indicates the pitch (e.g., 1.25mm or 20). 

Method 3: Checking the owner's manual or existing lug nut

1. Check the manual: Consult your vehicle's owner's manual, as it will usually list the correct lug nut size.
2. Inspect the lug nut: Look for the size to be stamped on the side of the lug nut. This is most common on lug nuts that have a chrome cap. 

How to find out wheel nut code?

Each key comes with a code so you can order a replacement from the vehicle manufacturer. The only place to find this code is on the locking wheel nut storage box or plastic storage bag – which is a problem if that's missing too!