What Is 700x38c Tire Size In Inches? (Best Answer)

So it’s time to change your bike tires, eh? Well, you might get a little confused with the number of options you find in the market. Depending on what sizing system you’re going by, the numbering will be totally different.

Didn’t you know? There are about three popularly used tire sizing systems for bicycles. And the worse thing is, they are all totally confusing! If your tire size is 700x38c, you might have to convert it into inches for some clarity.

So, what is 700x38c tire size in inches? Well, the simple answer is 27 ½’’by 1 ½’’ inches. So that means 27.50 by 1.50’’, to be precise. But although the answer seems pretty straightforward, there are loads of details worth discussing.

700x38c in inches

Why Do We Need The Tire Size In Inches?

Biking is one of the biggest industries in adventure sports, with millions of customers worldwide. You’d think that an industry as big as this would figure out a universal way of doing things. But think again, because your world is about to totally confusing and delirious.

As we mentioned earlier, there are three sizing systems that the bike industry uses today. These are the ETRTO system, the imperial system, and the metric system. If you find that confusing, you can also refer to them as the ETRTO, English, and French systems.

But why do we have so many tire sizing systems? Isn’t it better if we stick to one? You know so that there are no issues for us bikers?

Well, if that’s your question, you’re barking at the wrong tree. The reason why we have three confusing sizing systems is that the powers can’t agree with each other. The sizing system depends on the manufacturing companies, who all have agendas to stick to either one of the three. So, it looks like we’re stuck with it for now.

Understanding The Size Conversion Rates

In order to understand why someone would want tire sizes in inches, you have to understand how the size conversion rates work. Out of these sizing systems, both the metric and ETRTO systems use millimeters. On the other hand, the imperial system uses inches to measure tire size. So if you’re replacing an ETRTO or metric tire for an imperial system tire, you’ll have to do some size converting.

How To Find Out And Convert Your Bike Tire Size?

Finding out your bike’s tire size is one of the easier steps to replacing a tire. All you have to do is take a close look at your tire’s sidewall, which displays the tire number. You might want to get your reading glasses on as the numbers might be pretty camouflaged. However, if you keep looking, you’ll find a series of numbers that run along the line.

Now, depending on what company manufactured your tires, it could look contain just one sizing system or all of them. Either way, you should be able to find out just by reading it.

You’ll notice that each sizing system comes with two pairs of numbers. For example, the number 700x38c has two pairs, the first being 700 and the second being 38. The crucial detail to understand about these pairs is that they each signify a specific element of the tire size.

The first pair of numbers, 700, is the tire’s total diameter. This is basically the circumference of the whole tire from top to bottom. On the other hand, the second pair, 38, refers to the tire’s width. Alternatively, we can also call it the measurement between flange to flange. To explain, flanges are basically the flared edges of the barrel, both outboard and inboard sides.

Sometimes, you might notice that your tire size only reads one number and a letter, such as 650 B. Don’t be confused; this is just a number used for a standard size of 27.5’’ in diameter. So, you’ll still be able to find a counterpart for this, although it might be more tricky. But then again, converting between any two sizing systems is always going to be a matter of trial and error.

Be Aware, The Conversion Is Not Always Accurate

When you are looking at 700x38c tire size in inches, you are basically converting the size from metric to the imperial system. Obviously, you might occasionally replace your bike’s tire with a tire that uses a different sizing system. If that’s the case, you will have to convert sizes from the metric system to whatever sizing system your new tires come in. This can be the ETRTO system, or the imperial system, depending on the tire manufacturer.

Now, although you might not find much difference in the quality of these different tire brands, you will find that their measurements are totally different. For example, 700x38c tire size in inches converts accurately to 27.50 by 1.50’’. However, when you actually swap your tire for that size, you might find that it doesn’t fit.

Similarly, you might want a replacement for a 700x35c tire size in inches, which should come up to 27 ½’’ by 1 3/8’’ . But again, there might be small differences in the measurement that renders the replacement useless. As frustrating as that may feel, you have no option but to keep guessing the right measurement. Try going one size up or one size down, and you might find the right one. However, we wouldn’t be surprised if you give up halfway.

That’s why it’s our personal opinion to choose a new tire that sticks with the sizing system you’re familiar with. After all, why risk the chances of a hit and miss when you could have a sure thing?


While we have established that 700x38c tire size in inches converts accurately to 27.50 by 1.50’’, there’s always a chance of inaccuracies there. The bike industry is ridiculous, and so are their size conversion charts. So don’t expect to end up with the exact counterpart replacement.

If you are replacing your tire with a different sizing system, always remember that the replacement tire might not fit. You will have to keep trying out variations until you find one that is actually perfect. It’s all you can do until a permanent solution can be found.

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