How to Choose Tennis Strings:
The Complete Guide (2025)

Know Your Level & Swing Speed

Your playing level is the single most important factor in choosing a tennis string. It determines whether polyester is even suitable for you — and getting this wrong is the most common mistake recreational players make.

The core rule: polyester strings require fast swing speeds to perform well. If you can't generate the racket head speed needed to flex the string bed, poly will feel board-like, offer no power assistance, and put unnecessary stress on your arm.

Choose Your String Material

There are four main string materials, each with distinct performance characteristics. Understanding these is the foundation of making a good string choice.

Polyester (Co-Poly)

The most popular string type on the ATP and WTA tours. Polyester strings are stiff, durable, and provide exceptional control and spin potential. Their angular and textured profiles grip the ball and snap back quickly, generating topspin. The downside: they lose tension rapidly — approximately 30–40% of initial tension within the first 24 hours — and go "dead" after 20–30 hours of play. Stiff polyester strings (ERT 55+) should be avoided by players with arm issues.

Best for: Intermediate to advanced players, baseline grinders, heavy topspin players, string breakers.

Multifilament

Multifilament strings are constructed from hundreds of intertwined micro-fibres, closely replicating the feel of natural gut at a fraction of the cost. They're soft, arm-friendly, and generate power naturally through elasticity. Their ERT stiffness ratings typically fall between 15–40, making them the go-to choice for players with tennis elbow or wrist pain.

Best for: Beginners, recreational players, seniors, arm pain sufferers, players who prefer a soft, lively feel.

Natural Gut

Made from cow intestine, natural gut is the benchmark for playability, comfort, and tension maintenance. It holds tension better than any synthetic string and provides a unique combination of power, feel, and arm-friendliness. The drawbacks are cost (£40–£60 per set) and vulnerability to moisture. Roger Federer used natural gut mains for his entire career.

Best for: Players who can afford it, serve-and-volley players, players with arm issues who need the best comfort available.

Synthetic Gut

A single solid core with a wrapping of nylon fibres. Synthetic gut is the most affordable string type and performs well for beginners and casual players. It offers a reasonable balance of power and durability without the stiffness of polyester. It's often the default string used by racket manufacturers and stringing shops.

Best for: Beginners, budget-conscious players, juniors.

Hybrid Setups

A hybrid uses different strings in the mains (vertical) and crosses (horizontal). The most popular setup is polyester mains with natural gut or multifilament crosses — you get the control and spin of poly with improved arm comfort from the softer crosses. Federer used Wilson Natural Gut mains with Luxilon ALU Power crosses throughout his career. Hybrid setups are popular among players who want poly's spin benefits but find full poly too harsh. See our Polyester vs Multifilament guide for a deeper comparison.

Pick the Right Gauge (Thickness)

String gauge refers to the diameter of the string, measured in millimetres. It is one of the most underrated factors in string selection, directly affecting spin, power, feel, and durability.

The rule: thinner strings bite into the ball more, generating more spin and a livelier feel. Thicker strings last longer and suit players who break strings frequently. Most players are best served by 1.25mm (16L or 17 gauge) as a starting point.

Set the Right Tension

String tension is measured in pounds (lbs) or kilograms (kg) and refers to how tightly the strings are pulled during stringing. It has a direct effect on power, control, and arm comfort. Every racket frame has a recommended tension range printed on it — always string within this range to avoid frame damage.

Higher Tension (56–62 lbs)

Provides more control and a crisper, more precise feel. Reduces the trampoline effect of the string bed, giving the player more responsibility for generating power. Best for advanced players with fast, full swings who need to keep the ball in the court. Higher tension also amplifies the stiffness of polyester strings, so players prone to arm issues should be cautious.

Lower Tension (48–54 lbs)

Provides more power (larger trampoline effect), a more forgiving feel, and better comfort. The string bed flexes more on impact, absorbing shock and reducing stress on the elbow and wrist. Recommended for beginners, seniors, players with arm pain, and anyone using multifilament or natural gut strings. See our full tension guide for deeper guidance by playing style.

Match to Your Playing Style

Once you've identified your level and material, the final refinement is matching the specific string to how you actually play. Two advanced players can have very different string needs depending on whether one is a baseline grinder and the other a serve-and-volley player.

Quick-Pick Table: Which String Should I Use?

Use this table to find the right string based on your complete player profile. Match your row and go — or use the StringMatch tool to get a scored recommendation across all 73 tennis strings in our database.

Common Mistakes When Choosing Tennis Strings

1. Using polyester as a beginner

The most common and costly mistake. Polyester strings are everywhere and heavily marketed, but they are genuinely unsuitable for anyone without a fast, consistent swing. Using stiff poly as a beginner means you lose power, gain no real control benefit, and risk developing arm problems that can take months to heal. Stick to multifilament until you have solid technique.

2. Playing on dead strings

Polyester strings lose approximately 30–40% of their tension in the first 24 hours after stringing. After 20–30 hours of play, the string bed "dies" — it loses elasticity and snapback, and the string becomes essentially a rigid board. Many club players play on strings that are months or years old. Dead strings cause arm injuries far more often than fresh ones, because the string can no longer absorb shock effectively.

3. Copying professional players

Pros restring before every match — sometimes multiple times during a match — and have personal stringers. They use stiff polyester at high tensions because they generate enormous swing speed that activates these strings. A recreational player using the same setup Novak Djokovic uses will get none of the benefit and all of the arm stress.

4. Ignoring gauge

Many players obsess over brand and material but overlook gauge. A 1.20mm string can feel dramatically different from a 1.30mm string of the same model. If you're breaking strings too quickly, go thicker before you go to a completely different string.

5. Stringing too tight

Higher tension does not always mean better performance. Beginners and players with arm issues who string at 60 lbs get a stiff, unforgiving feel with no power benefit. String within the frame's range, and start at the lower-to-mid end unless you have a specific reason to go higher.