Synthetic string technology has improved dramatically over the last 20 years and there are very few “bad” strings. However, not all strings (and string tensions) are right for all players. Every player has different needs and preferences. Here are a few guidelines to make your string and tension selection easier.

Playability

It’s very difficult to obtain consensus on what makes a string playable. Some players like a crisp, firm playing string while others equate playability with softness and comfort. Generally, a playable string is resilient, which means it snaps back quickly upon ball impact. The material, construction, and thickness of a string will all affect the playability of a string. The most resilient (playable) string at this time is still natural gut. This is the only string made from a natural product - beef intestines. It is the oldest tennis string made and remains the benchmark for playability. Some of the most popular playability strings at Tennis Warehouse include: Babolat X-Cel, Prince Premier w/SoftFlex, Tecnifibre NRG2, Tecnifibre X-One BiPhase and Wilson Sensation NXT. Strings that offer good playability at a lower price (below $7.00) include: Alpha Gut 2000, Ektelon PowerPlay (AKA Prince Synthetic Gut Soft) and Tecnifibre E-Matrix.

Durability

As with our beer, most of us want a string that offers everything. Unfortunately, increased durability in tennis strings is usually at the expense of playability. Thicker gauges and abrasion resistant materials will be more durable, but they are less elastic and resilient than their thinner, nylon-based counterparts. (See gauge table below.) If a player is breaking a 16 gauge nylon string (synthetic gut), we might suggest they switch to a 15L version of that same string, if available, for more durability. Otherwise, the next step would be a nylon durability string, such as Gamma Marathon DPC or Wilson Stamina. After that, we recommend trying a polyester string, such as Babolat Ballistic or one of the popular Luxilon strings. Finally, for players who blow through all of the strings listed above, Kevlar hybrids are the final alternative. The superior abrasion resistance of Kevlar makes it the most durable string available.

String Gauge

Generally speaking, thinner strings offer improved playability while thicker strings offer enhanced durability. Tennis string gauges range from 15 (thickest) to 19 (thinnest), with half-gauges identified with an L (15L, 16L, etc), which is short for “light”. A 15L string is thinner than a 15 gauge but thicker than a 16 gauge string. Thinner strings also provide more spin potential by allowing the strings to embed into the ball more.

String Gauges and Diameters in millimeters

Below are the Tennis Industry Association's gauge standardization specifications. The string gauge is usually measured with the string under tension. For example, a string that measures 1.26 mm unstrung would appear to be either a 16 or 16L. When strung, however, the diameter might become 1.21, which would make it a 17-gauge string.