Tennis Racket Stiffness Explained


If you’re busy browsing the tennis racket market, you are likely trying to make sense of all of the numbers you’re seeing. The racket’s “specs” show everything you really need to know about each racket, and they will give you the best idea of what a racket will play like before you even hit a ball. One of the most telling specs is racket stiffness, and it’s important to understand what that number means before you consider buying a particular racket.

A racket’s stiffness is defined by how much the frame bends when it makes contact with the ball. The number you see is correlated directly to how much the racket is distorted as the ball is struck. So, a higher rating of stiffness relates to less bend in the racket at contact. A lower rating, therefore, means that a racket will bend more at contact. 

Rackets on the market have a stiffness of anywhere from 40-80. However, the most popular rackets typically fall between 60 and 70. The difference between a racket with a rating of 60 and a racket with a rating of 70 quite substantial.

This article will go through the details of what stiffness means, how stiffness affects a racket’s feel, how stiffness affects potential injuries, and examples of rackets with both high and low stiffness ratings. Let’s get to it.

What does stiffness mean in a tennis racket?

We touched on it above, but stiffness is defined by how much the frame bends when it makes contact with the ball. “Stiff” rackets are less distorted at impact than “flexible frames, assuming that all of the other specs are the same. 

The stiffness in a racket is one of the most important specs because it considerably affects how a racket will feel to a player upon contact. This number tends to confuse people and to be honest, it confused me as well earlier in my career.

When we say that a racket is distorted at impact, this isn’t something apparent to the naked eye. Flexible rackets aren’t going to be bending to the point where you’ll see it when hitting a ball, but players will definitely feel a difference in how the ball comes off the strings. 

How is stiffness determined?

So if you can’t see the racket bend, how can people tell how stiff a frame is? You can’t bend even the most flexible frames on your knee and expect to see anything. If you try this, you may be looking like Stan Wawrinka below. 

There are machines that determine a racket’s stiffness. These machines are used by racket companies to put a number on the rating so that their consumers have a better idea of how the racket will play. 

How does stiffness affect a racket?

Now it’s time for the important part: Why does stiffness matter? The stiffness determines how much control and feel the racket has. This is why this spec should be such a key factor when deciding which racket you should be using.

The reason that this rating is confusing to many is because the wording is slightly contradictory. Some players jump to the conclusion that the higher stiffness rating will cause the racket itself to feel stiff, like a board (i.e more control, less power). The truth is actually the opposite. Remember, stiffer rackets actually allow for more power, not less. 

Sounds weird, but once it is explained it will make some more sense. Stiff frames allow the energy to bounce back quickly and explosively off of the strings at impact. The stiffer the frame, the less energy is transferred to the racket (and therefore there is more energy in the ball). Frames that are less stiff absorb more energy from the ball, and therefore the racket will provide less power when the ball is transferred off of the strings. 

Does stiffness increase the risk of tennis elbow?

This is a common question. The answer is yes, definitely, but it is not the only spec that can contribute to injury. The combination of a stiff and light weight racket can cause injury because of the way the joints are whipped around, especially with hitches in technique. Less stiff rackets can also lead to injury, mainly if they are heavy, because the joints end up taking a lot of the blow at contact when the racket does not bend.

The stiffness of your racket could be leading to injury, but it isn’t always as simple as just using a racket that has a different stiffness. It is important to look at the whole picture rather than just one spec of the racket. 

For more information about tennis elbow, see our article: Tennis Elbow – The Full Guide For Tennis Players.

Recommendations and Examples

Now that you have a better understanding of what stiffness is all about and what it can provide to your game, you are ready for a couple of our recommendations. Remember that stiffness is just one of the many factors that makes a racket more based in power or control, so stiffness is not the ultimate determiner. Below are our highly recommended rackets for both low and high stiffness. 

Stiff Rackets

Wilson Ultra 100 v3

Stiffness of 73

Babolat Pure Aero

Stiffness of 67

Babolat Pure Drive

Stiffness of 71

Wilson Pro Staff 97 RF Autograph Black

Stiffness of 68

Flexible Rackets

Yonex VCORE PRO 97HD 18×20

Stiffness of 59

Wilson Blade 98 18×20 v7

Stiffness of 62

Head Gravity Tour Graphene 360+

Stiffness of 61

Head Graphene 360+ Prestige Midplus

Stiffness of 61

Final Thoughts

When choosing a racket, it is important to understand the specs that the racket provides. The combination of all these specs is what makes a racket unique, and they will give you an idea of what a racket will play like before you even hit a ball.

Stiffness is one of the specs that generally has a large effect on how a racket feels, so hopefully this article answered some of your questions about it. If you have more detailed questions that we may have missed the answer to, feel free to reach out to us. You can reach us either in the comments below this article, or on our instagram at @MyTennisHQ.

Austin Rapp

Hi there! My name is Austin Rapp and since I picked up a racket at age 8, I worked hard to improve my game. I was never the most talented junior, but I tried to learn the game to give myself an edge. I earned the privilege of playing at UCLA for 4 years, serving as team captain for my last 2. In my time there, I took advantage of the coaching and great talent around me to grow my knowledge of the game and became an All-American. I am currently playing professional tennis, ranked top 700 in singles and top 350 in doubles. Above all, my favorite tennis moments were hitting with Roger Federer and Rafa Nadal at Indian Wells!

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