Know Your Strings

String is one of the most important gears for tennis players as they dictate 3 important element of the game – Spin, Control & Power. No matter how good a tennis racquet is, a bad string can seriously hamper the performance. Effectively, strings make or break the game and hence all good tennis players lay a lot of emphasis on strings.

Here is a short primer onTennis String from’s inhouse tennis expert.

String Materials

Strings offer different characteristics based on the material they are made up of.

Natural Gut – As the name suggests, this is a natural product made from the gut of animals (mainly sheep). This type of string is still favored by the purists for its optimum mix of power, control and spin. It is, however, the most expensive and least durable of all the strings. It is also susceptible to extremes in temperature and is especially liable to break under damp or wet conditions. There is no man-made string exactly like natural gut but some of the multifilament strings come close.

Synthetic Gut – These are an extension (and improvement) on nylon strings to compensate for the lack of durability from natural gut. The majority of factory strung rackets are strung with synthetic guts and are a good choice for most people. They give a good mixture of power and control with a “crisp feel and sound”. They do not offer much potential for spin, however, unless you choose a “textured or spin” type synthetic gut string. Synthetic strings are good on their own or in combination with more durable kevlars and polyesters.

Multi-filaments – These are the best examples of using technology to replicate a product that has been successful over a number of years (natural gut). Thin strands are wound around (just like natural gut) to create different variations of spin, power, control and durability. Multifilaments are a good choice for the majority of players as they offer the optimum mixture of playability and durability. They are not as durable as the polyesters but are definitely better on the arm. In fact, for anyone suffering from tennis elbow or any kind of arm problems, multifilaments are the best thing to go for.

Polyesters – Polyester is a durable fiber with a thin coating, and is best for players who tend to break strings more frequently. Compared to other synthetic materials, polyester is very firm and difficult to snap. Polyester generates more topspin than other strings because they don’t slide around during contact with the ball. Many professional players have a high preference for polyester strings because of its ability to generate huge amounts of topspin.

Hybrid Combinations – The majority of people now use the polyesters as a hybrid by combining them with a synthetic gut or multifilament string. The general rule is to use the polyesters (harder string) on the mains and anything else on the crosses.

String Tension

The string tension affects a racquet's playing characteristics, such as the "feel" of the ball, control over the ball, as well as power. All racquets come with recommended string tensions, most of which lie between 50 to 70 pounds. It is advised by many professional stringers to string your racquet with the lowest tension possible while still being able to maintain control of the ball. Beginning players should start in the middle of the recommended tension range and adjust the tension from there to meet their needs. The recommended tension is usually printed on the racquet.

Tighter strings mean more shot control and spin, so they are probably better if you’re trying to hit the ball harder and improve accuracy. Looser strings mean more power but less control. More experience players tend to play with high string tension for better control.

One must be careful about going to extremes with string tension as very tight strings can have a damaging impact on the arm and contribute to injuries. It is recommended that you always have your racquet strung within the manufacturer’s guidelines.

String Guage

Guage means the thickness of the string. Tennis strings have a special scale to measure the guage.

As a general rule, thinner strings offer improved playability while thicker strings offer enhanced durability. Tennis string gauges range from 15 (thickest) to 19 (thinnest), with half-guages identified with an L (15L, 16L etc). A 15L string is thinner than a 15 guage but thicker than a 16 guage string. Thinner strings also provide more spin potential by allowing the strings to embed into the ball more.

String Guages and Diameters in millimeters:

  • 15 = 1.41 – 1.49 mm
  • 15L = 1.34 – 1.40 mm
  • 16 = 1.26 – 1.33 mm
  • 16L = 1.22 – 1.26 mm
  • 17 = 1.20 – 1.24 mm
  • 17L = 1.16 – 1.20 mm
  • 18 = 1.10 – 1.16 mm
  • 18L = 1.00 – 1.10 mm

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