How To Measure Bicycle Wheel Size? Easy Method

How To Measure Bicycle Wheel Size? Easy Method

Are you curious about how to figure out the size of your bicycle wheel?

No worries, we’ve got your back! Whether you’re a bike enthusiast or just want to know more about your trusty two-wheeler, this article is here to help.

So, saddle up and get ready to uncover the secrets of measuring your bike wheel size.

From understanding diameter and radius to deciding whether to measure the whole wheel or just the rim, we’ll guide you through it all in a fun and straightforward way.

Let’s hit the road and learn how to measure your bike wheel size like a pro!

The Two Measuring Methods

Before we proceed to how to measure your bike wheels, we need to understand the different methods used.

There are two methods to measure bikes wheels:

  • ISO Method
  • Standard Method

The difference between the ISO method and the standard method lies in how they measure and indicate bicycle tire sizes.

ISO Method

The ISO method is a standardized system that provides a clear and consistent way to represent tire sizes.

It uses a series of numbers to indicate the tire’s width and diameter.

For example, a common ISO size is 700c x 25, where “700c” refers to the wheel diameter and “25” represents the tire width in millimeters.

This method ensures compatibility and makes it easier to match tires with appropriate rims.

Standard Method

The standard method, also known as the traditional or inch-based method, relies on imperial measurements, specifically inches.

It typically uses a combination of fractional numbers and inch designations to represent tire sizes.

For instance, you might come across sizes like 26 x 1.95 or 27.5 x 2.1.

The first number indicates the approximate outer diameter of the tire, while the second number represents the tire width in inches.

The ISO method offers a more precise and standardized approach, especially when it comes to matching tires with compatible rims.

It simplifies the process and provides greater accuracy in selecting the appropriate tire size for your bike.

However, the standard method is still widely used, particularly in older bikes or certain cycling disciplines.

Overall, while the ISO method is becoming more prevalent, it’s essential to be familiar with both methods to ensure you can choose the right tires and maintain compatibility with your bike’s wheels.

How To Measure Bicycle Wheel Size?

To measure wheel size using the standard method in inches, you’ll need a tape measure or ruler.

Here’s how you can do it:

1. Remove the Wheel

If the wheel is still attached to the bike, take it off to get accurate measurements.

I assume you know how to take the wheel off.

If you are unsure how to do it, refer to your bike’s manual.

2. Locate the Diameter

The diameter is the distance across the wheel from one side to the other, passing through the center.

Using your tape measure or ruler, place it horizontally across the wheel’s center.

3. Measure the Diameter

Align the tape measure or ruler with the outer edge of the rim on one side, and extend it to the outer edge of the rim on the opposite side.

This measurement will give you the approximate diameter of the wheel in inches.

4. Record the Measurement

Note down the measurement you obtained.

For example, it might be 26 inches or 27.5 inches.

5. Confirm the Wheel Size

Verify the measurement by cross-referencing it with any markings on the tire or rim.

Some tires have the wheel size printed on the sidewall, such as “26 x 2.0” or “27.5 x 2.1”.

This can help ensure the accuracy of your measurement.

Note: in the standard method of measuring wheel size in inches, you should measure the entire wheel, including both the rim and the tire.

Using the standard method, you are primarily interested in the diameter of the wheel, which represents the distance from one side of the wheel to the other.

How To Measure Bicycle Wheel Size ISO Method?

Measuring bicycle wheel size using the ISO method is quite straightforward.

Here’s a step-by-step guide in easy language:

Look for the ISO Markings: On the sidewall of your tire, you’ll find markings indicating the ISO size.

It will typically be in the format of something like “ISO 622” or “ETRTO 32-622”.

ISO stands for International Organization for Standardization, and ETRTO stands for European Tyre and Rim Technical Organization.

Identify the First Number: The first number in the ISO marking represents the wheel diameter.

For example, if you see “ISO 622”, it means the wheel diameter is 622 millimeters.

Understand the Second Number: The second number in the ISO marking indicates the tire width. It represents the measurement in millimeters from one side of the tire to the other. For instance, in “ETRTO 32-622”, the tire width is 32 millimeters.

Note Down the ISO Size: Record the ISO size, including both the wheel diameter and tire width.

For example, your tire’s ISO size could be “622 x 32”.

Not all wheels have the size written down on them

While many modern bicycle tires and rims do have size markings, especially those following the ISO or ETRTO standards, it is not a universal requirement.

Some older or lower-quality tires may not have visible size markings.

In such cases, it becomes necessary to measure the wheel manually to determine its size accurately.

This can be done by measuring the diameter of the wheel, as explained above.

If you are unsure about the size of your wheel and cannot find any visible markings, measuring the diameter of the wheel or consulting a bike professional at a local bike shop can help you determine the correct size for replacement tires or other components.

Which Measuring Method Is Better?

Both the ISO method and the standard method have their advantages and are widely used in different contexts.

The “better” method depends on your personal opinion, the type of bike you have, and the availability of compatible tires and components.

Here’s a comparison to help you understand:

ISO Method:

  • Standardized: The ISO method provides a standardized system for specifying tire and wheel sizes, ensuring consistency and compatibility.
  • Precise: The ISO method uses specific numbers to represent the wheel diameter and tire width, offering more precise measurements.
  • Widely Accepted: The ISO method is commonly used in the cycling industry and is preferred for its accuracy and compatibility.

Standard Method:

  • Historical Usage: The standard method has been used for a long time and is still prevalent, particularly in older bikes or certain cycling disciplines.
  • Familiarity: Many cyclists are accustomed to the standard method and find it easier to understand and remember sizes using inches or fractional measurements.
  • Availability: Replacement tires and components are often labeled using the standard method, making it convenient for those using this system.

The ISO method offers standardized accuracy, while the standard method has historical familiarity.

It’s important to understand both methods and choose the one that best suits your needs and the specific requirements of your bike.


In conclusion, measuring your bike’s wheel size is a simple task that can be done with a tape measure or ruler.

By following a few easy steps, you can quickly determine the wheel diameter and have the measurement at your fingertips.

This knowledge comes in handy when you need to replace tires, select compatible components, or communicate your bike’s size to others.

Having the correct wheel size ensures a proper fit and optimal performance for your bike.

Whether you ride a mountain bike, road bike, or any other type of bicycle, knowing your wheel size allows you to make informed decisions when it comes to maintenance, upgrades, or repairs.

So, don’t hesitate to take a moment and measure your bike’s wheel size—it’s an essential skill that every cyclist should have.

Frequently Asked Questions

Here’s a list of the most asked questions about wheel measuring, answered for you:

Q: Are bike Wheel Sizes Measured in inches or Millimeters?

A: Bike wheel sizes can be measured in both inches and millimeters.
However, the most common practice is to use inches for standard measurements and millimeters in the ISO (International Organization for Standardization) method.

Q: What Is The Difference Between the ISO Method and the Standard Method for Measuring Wheel Sizes?

A: The ISO method provides standardized measurements for bike tires and rims, using specific numbers for diameter and width.
The standard method often uses inch-based measurements and is still prevalent, particularly in older bikes or specific cycling disciplines.

Q: Are There Specific Wheel Sizes For Different Types Of Bikes?

A: Yes, different types of bikes often have specific wheel sizes associated with them.
For example, mountain bikes commonly have 26-inch, 27.5-inch, or 29-inch wheels, while road bikes often use 700c wheels.

Q: Can I Replace My Bike’s Wheels With A Different Size?

A: It is generally recommended to replace your bike’s wheels with the same size or a compatible size to ensure proper fit and performance.
However, in certain cases, such as upgrading to a larger wheel size or adapting to specific riding needs, a change in wheel size may be possible with appropriate adjustments.

Q: How Do I Find The Right Tire Size For My Bike’s Wheel?

A: The appropriate tire size for your bike’s wheel can usually be found on the tire sidewall, indicated by a series of numbers.
It may follow the ISO or standard method, such as “26 x 2.0” or “700c x 25mm”.
Ensure that the tire size matches the wheel size and consider factors such as tire clearance and intended use.

Q: Can I Use Different Wheel Sizes On The Front And Rear of My Bike?

A: It is generally recommended to use matching wheel sizes on the front and rear of your bike for optimal handling and performance.
Using different wheel sizes may affect the bike’s geometry and stability.

Q: How do I know if a specific wheel size is suitable for my height?

A: While wheel size is not directly determined by height, it can be a factor in choosing the right bike size.
It’s recommended to refer to bike manufacturer size charts, which provide recommendations based on height and inseam measurements, or consult with a bike shop professional for personalized advice.

Q: Can I Convert My Bike’s Wheel Size To a Different Measurement System?

A: Yes, it is possible to convert between different measurement systems.
Online conversion charts and calculators can help you convert wheel sizes from inches to millimeters or vice versa.

Avatar photo
Joey B. Ramsey
Passionate cyclist, father, and blogger.
I've been riding bikes since childhood and enjoy sharing my knowledge with fellow cycling enthusiasts.
My diverse bike collection allows me to write reviews and advice based on personal experience with various bikes and accessories.
join me email cta
Join me
Join me for more cycling related content and deals.

Related Articles