The Complete Guide to Understanding Tennis Racket Stiffness

The stiffness of a tennis racket is an often-overlooked yet decisive parameter. Even more than weight or head size, it directly influences your feel, your performance, and even your health. Let's dive into this masterclass together to demystify this key criterion.


What is stiffness (RA)?

Stiffness is measured by the RA (Stiffness Rating) index. This index indicates how much the frame deforms upon impact:

Stiffness (RA) Scale and Playing Characteristics
Type RA Index Characteristics
Very Flexible < 60 Maximum flexibility, high comfort
Flexible to Medium 60–65 Good compromise between control / comfort
Stiff 66–70 Natural power, less forgiveness
Very Stiff 70+ Maximum explosiveness, more vibrations
The RA measurement quantifies the deformation of the frame upon impact.

The Direct Impact on Your Game

Stiff Racket

  • Increased natural power ("trampoline effect")
  • Reduced dwell time → trickier control
  • Stronger transmission of vibrations

Flexible Racket

  • Less intrinsic power
  • Superior control thanks to "pocketing"
  • Playing comfort, shock absorption

How to Choose Based on Your Profile?

For the Beginner / Intermediate Player

  • Choose a flexible to medium (60–65 RA) racket
  • Helps develop technique → longer contact time
  • Better comfort and protection for joints

For the Seasoned Competitor

  • Opt for a stiffer racket (66–70+ RA)
  • Increased stability and immediate power
  • Reserved for physically solid players

Based on Playing Style

  • Power Hitter → Stiff frame
  • Touch Player → Flexible frame
  • All-Around Player → Medium RA

Myths & Realities

“A flexible racket isn't powerful”
False: A player with high swing speed can generate a lot of power even with a flexible frame.

“Stiffness is the only factor for comfort”
False: String, tension, balance, and weight also play a major role.

“All pros play with stiff rackets”
False: Some prefer flexible frames for touch and arm protection.


Key Takeaways

Stiffness is a dialogue between your body, your technique, and your intentions on the court. Test different models, listen to your feel, and choose a racket that gives you confidence and protects your arm. Discover our complete selection of tennis rackets to compare RA ratings and find the model that's right for you.