Open vs Closed Tennis String Patterns

The string pattern in your racket is one of the biggest factors in how you play.

An open pattern like 16x19 or 16x18 gives you more spin, more power, and a higher launch angle with a softer feel.

A closed pattern like 18x20 gives you more control, a flatter trajectory, and longer string life with a firmer feel.

In this guide you will learn what string patterns are, how open and closed patterns play, and how to pair the right string with your pattern to get the most out of your setup.

Characteristic	Open (16x19, 16x18)	Closed (18x20)
Spin	Higher	Lower
Power	Higher	Lower
Launch	Higher	Flatter
Feel	Softer	Firmer
Control	Less	More
Durability	Shorter	Longer

What Are String Patterns?

Look at your racket face and you will see strings running two ways. The vertical strings are your mains and the horizontal strings are your crosses.

The string pattern is written as a formula, the number of mains by the number of crosses. For example, a 16x19 pattern has 16 main strings and 19 cross strings.

The most common patterns are 16x19 and 16x18 (open), and 18x20 (closed).

Your string pattern is fixed to the frame, much like head size. Stringing cannot change it, so it is a spec you choose when you buy the racket.

Finding your pattern is easy. Most frames print it near the throat or on the shaft, and if yours does not, you can count the mains and crosses yourself.

No pattern is inherently better than another. The right one for you depends on how you play and how you like the ball to feel at contact.

Here is how the two compare across the playing characteristics that matter most.

Open String Patterns (16x19, 16x18)

Open patterns like 16x19 and 16x18 offer more spin and power than closed patterns.

For example, world number one Jannik Sinner plays a 16x19 in his HEAD racket, and the pattern is a favorite of aggressive baseliners for good reason.

The wider gaps between strings give the stringbed more room to move. When you strike the ball, the strings move, grip, and snap back with force, which adds pace and rotation.

That movement brings easier spin, more free power, and a higher launch angle that helps you clear the net and hit with depth.

The softer response of open patterns also feels more forgiving, which many players managing arm issues prefer.

The downsides of open patterns come in control and string life. You give up some directional precision, and because the strings slide and snap on every shot, they notch and wear faster.

However, you can extend the life of your stringbed by playing with strings like reString Zero, reString Slap, and reString Sync that are built to play better for longer.

Closed String Patterns (18x20)

Closed patterns like 18x20 offer more control than open patterns.

For example, Aryna Sabalenka swings big with an 18x20 in her Wilson racket, using the density to keep her aggressive, flat groundstrokes in the court.

The tighter spacing packs the strings into a compact, uniform stringbed. There is less room for the strings to shift, so the response stays consistent from one shot to the next.

That consistency creates precise directional control, a flatter trajectory that drives through the court, and predictable feedback on every strike.

The restricted string movement also means far less friction, so your strings last longer.

The downsides of closed patterns are that you get less free power and spin, the sweet spot feels slightly smaller, and the firmer stringbed gives a stiffer feel at contact.

Hybrid String Patterns (16x20, 18x19)

If you want a mix of traits, you can play with a hybrid pattern like 16x20 or 18x19.

A 16x20 keeps the spin-friendly open mains but adds an extra cross string to tighten the response. For example, Carlos Alcaraz plays a 16x20 in the Babolat Pure Aero 98.

An 18x19 keeps the precision of a closed pattern while dropping one cross string to allow a little more string movement and spin. Novak Djokovic uses an 18x19 in his HEAD racket for exactly that.

Pairing Strings With Your Pattern

As important as string pattern is, your racket is only one half of your setup.

Your strings are the other half, and the string you choose can either boost your pattern's natural traits or balance them out.

To boost, match your pattern to a string that shares its character.

An open pattern with a power and spin string like reString Zero or reString Slap pushes power and spin even higher. A closed pattern with a control string like reString Sync sharpens control and feel.

To balance your string pattern out, do the opposite.

reString Sync in an open pattern steadies the launch angle. reString Zero or reString Slap in a closed pattern adds power and liveliness to a firmer stringbed.

String gauge is another lever for fine-tuning.

If you have a closed pattern but want to open it up, a thinner 17G or 18G gives you more spin and a friendlier launch angle. The same works in reverse for open patterns.

Frequently Asked Questions

Is 16x19 or 18x20 String Pattern Better?

Neither is better on its own. The right choice depends on your playing style. Go with a 16x19 if you want spin, easy power, and a forgiving feel. Choose an 18x20 if you want precision, a flatter trajectory, and longer string life.

What String Pattern Is Best for Topspin?

An open pattern like 16x19 or 16x18 gives you the easiest access to topspin. The extra room lets the strings move and snap back to grip the ball. The trade-off with this kind of pattern is durability, since more movement means faster wear.

What Is the Best String Pattern for Tennis Elbow?

Open patterns tend to feel more forgiving on the arm because the strings move more on impact and absorb more of the shock. Pair an open pattern with the right string type and a comfortable tension for the most arm-friendly setup you can build.

Summary

String patterns are how many main and cross strings are in your racket, ranging from 16x18 to 18x20. The best one for you comes down to how you play.

Open patterns give you spin and power, closed patterns give you control and predictability, and hybrid patterns land somewhere in between.

The pattern sets the foundation. Your string completes the setup, either boosting the pattern's natural strengths or balancing them out.

Once you know your pattern, the next step is finding the string that fits it.

Use our String Finder to find a string that works perfectly for your game.

About the Author: Juan is the co-founder of reString. He was born in Argentina, raised in Japan, and moved to the US to pursue college tennis. He now plays as an ATP & WTA hitting partner.