Tennis string types explained

The four materials

Everything sold as tennis string belongs to one of four material families, and the families differ far more from each other than the brands differ inside a family. Understanding the four takes about two minutes and saves most of the money people waste on string.

Synthetic gut

A solid nylon core with one or more wrapped outer layers, usually with a wear-resistant coating. It is the cheapest real string there is — Tennis Warehouse list Prince Synthetic Gut Duraflex at $4.76 a set — and it is deliberately unremarkable in every direction. Reasonable power, reasonable comfort, reasonable durability, no particular strength.

Multifilament

Hundreds or thousands of fine fibers bonded together, usually with polyurethane. Wilson NXT is built from over a thousand fibers and is Tennis Warehouse's comfort winner at $23.95. Because a bundle of fibers stretches further than a solid core, multifilament is the softest and most powerful of the synthetic types, and it frays rather than snapping cleanly.

Polyester

A single stiff monofilament, sometimes with a shaped or textured profile. Solinco Hyper-G at $13.99 and Luxilon ALU Power at $21.50 are both in this family. Poly holds its shape under load instead of stretching, which produces a lower launch angle, more control and much better durability — and it is the stiffest, least forgiving option by a wide margin.

Natural gut

Made from processed cow intestine, and still the best-playing string material available: the most comfortable, the most powerful and the best at holding tension. It is also the most expensive and the least tolerant of moisture. We do not currently carry a natural gut listing we are confident in, so there is no pick for it below — naming nothing is better than naming something unverified.

Hybrids: using two types at once

A hybrid is one material in the main strings and another in the crosses. It exists because the two directions do different jobs: the mains take most of the wear and do most of the work generating spin, while the crosses contribute more to the overall feel of the bed.

The common configuration is polyester mains with a multifilament or synthetic gut cross. That gives you the durability and the spin behaviour of poly where the wear happens, and some of the comfort of a soft string where it costs you least. It is a genuine middle path rather than a marketing construct.

Two honest caveats. A hybrid costs a set of each string rather than one set, so it is not cheap, and it is a harder setup to interpret — if the bed feels wrong you now have two variables to adjust rather than one. Most players are better off getting a single-material setup right first.

Gauge is a separate decision from type

Gauge is the thickness of the string, and it runs backwards: a higher number is thinner. Our registry spans 15L at the thick end to 20 at the thin end, with 16 and 17 covering most of what people actually buy.

• Thinner (higher number) — more feel, more spin potential, more power, and it breaks sooner. Thin strings also bite into the ball more, which is where the extra spin comes from.
• Thicker (lower number) — more durable, slightly more controlled, less feel. The right direction if you are breaking strings but do not want to leave a soft material.

Gauge interacts with type in one useful way. If a multifilament is nearly lasting long enough but not quite, going a gauge thicker can get you there without moving to polyester — which is a far bigger change in how the racket plays. Tennis string gauge covers the trade in full.

Choosing your type in one question

Everything above collapses into a single decision, and it is not about your rating, your frame or your favourite professional. It is about how long a set of string currently survives in your racket.

If you have never broken a string, the last row is important and it catches most club players out. Strings die of tension loss long before they break, and a bed that has gone dead plays worse than one that has snapped — because at least a snapped string tells you. How often to restring a tennis racket covers the schedule.

How this guide was put together

We do not run a test lab and nothing here is written as though we did. This guide is built from the published specification sheets and third-party lab measurements cited at the foot of the page, plus the physical reasoning that connects them. Where a figure is not published we say so rather than estimating it.

The picks below are drawn from our product registry, so every one carries a cited source and a verified listing. Our full selection criteria set out the method and the editorial policy covers corrections. No price is written into this page — the figure on each buy button is the live one.