What Are 700x45c In Inches Bike Tires?

Bike tires with a ‘700c’ dimension written on the tires belong to the French sizing system, which is one of the biking industry’s most common measurement standards. The French sizing system is in addition to the ISO, English, and other measurement systems all around the world. 

But unless you are a biker or work in the bike industry, stamps such as 700x45c in inches written on the tires may not make a lot of sense to you if you’re curious about the numbers on your bike tires and what they could possibly mean, here is the answer. 

Although the simple answer to 700x45c in inches translates to 27.5 inches and 1.77 inches.

700x45c in inches

What Does It Mean If A Bike Tire Has 700x45c Written On It?

The 700 refers to the nominal diameter of the bike tire, while the 45 refers to the width of the bike tire. The letter ‘c’ is a width code used in the French sizing system, especially in the olden days. This coding on bike tires means it is wider than a tire marked ‘b’ but is narrower than another one with a ‘d’ on it. 

Until a few years ago, 700c bike tires were mostly a feature that was common in hybrid and gravel bikes and very rarely on track and road bikes. But you will see 650b wheels on these bikes, especially in the newer ones.

In addition, most manufacturers make road bike tires with a 700c measurement, which you can easily swap with gravel or hybrid bikes with a 650b measurement if you wish. 

Is 700x45c In Millimeters The Same As The One In Inches? 

Not exactly. This is because the French sizing system measures the tires in millimeters, while the ISO, which is the international standard in most countries, measures the tires in inches. In addition, bike tire measurement tends to vary from country to country. 

Therefore, 700x45c in inches is very different from one written in millimeters. In addition, two bike tires that are measured in inches can have different sizes. For instance, a bike tire with 1.75 inches is usually different from one that says 1 ¾ inch.

Using the wrong-sized tire on your bike comes with several disadvantages, including discomfort while riding, tire being punctured more easily, and of course, the compromise on the overall performance. 

Is 700x45c The Right Tire For You?

700x45c bike tires are not your average road bike, so it is not for everyone. Bike tires with a width of 45 millimeters are quite large and come with many advantages, including better traction and corner grip. In addition, these tires are also inflated to lower pressure, so they have better contact with the road surface. 

Tires with a 45c width are ideal for you if you frequently explore gravel roads for recreation or competition. You will also love the 700x45c bikes if you enjoy testing the limits and conditions of the different terrain on the road. 

Tires of this width have more air volume in comparison to narrower tires, which adds an element of comfort. With the increased air volume and the extra comfort, you can take the 45c tires literally anywhere without compromising on speed or performance. 

If you decide to go for a 45c width tire, 700c wheels are the perfect configuration. But you could also optimize your bike’s performance with a 650B wheel. 

However, a bike with a 45c tire may not work for you if you ride pavements a lot, as the tires are more sensitive to pressure. Depending on the treads, bike tires of this size can also make considerable noise on the pavements. 

How Do I Pick The Right Tire For My Bike?

For picking the right tires for your bikes, a rule of thumb is to check the dimension of the old tire. The sidewall of the bike tire is where you will find the dimensions stamped by the manufacturers, so that is where you should look.

Additionally, while getting new bike tires, make sure they have the same dimensions as the old ones. Getting the right bike tires is essential as it can determine the overall performance as well as comfort. Fitting your bike with the right tires will also prevent it from puncturing easily and will, therefore, last longer. 

It’s the same as fitting the bike with the right inner size tube. For instance, when you want to replace inner tubing, you ask and wonder what size inner tube for 26 x 1.95 would be a perfect fit for your bike tires that measure 26 inches. 

For picking the best bike tires, here are a few pointers

Look at the tread patterns that are open along the tires’ sides but are tightly packed with rubber lugs towards the center of the tire. 

The open tread pattern on the edges allows the tire to have a solid grip irrespective of the surfaces – gravel or dirt. In addition, the tight pattern at the center is fantastic for riding on paved and other similar surfaces. 

If you’re looking for a recommendation, 700x45c bike tires from Maxxis and Pirelli are a great pick. These tires have open treads on the edges and tight rubber lugs at the center of the tire, which gives them a good grip on multiple surfaces. 

Bike tires of this width from Kenda Khan are also great. The treads on the tires are different, but they perform fantastically and are a favorite of pro riders. 


Choosing a tire for your bike is not as straightforward. Bike tires, whether MTB, gravel, or road bikes, have different measurement standards, which can make it tricky to pick the right fit. 

Beginners looking for the perfect tire for their bikes can find it even harder because tires measured in inches can also be different in actual sizes, as we’ve mentioned above. 

Regardless of the sizes and what measurements are written on your bike tires, if you’re looking to change them, pick the tire with the exact designations written on the old ones. If you want to change other bike components, including the inner tubes, the same tip also works great. 

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