How to choose tennis strings? The complete string guide.

Tennis strings might just be the most underrated part of all tennis equipment. Many players know by now how much the right racket and shoes affect their enjoyment and performance on court. Unfortunately, they often pay less attention to their strings, and end up playing for months or even years with a string bed that has long since seen better days.

Just like your racket and shoes, your strings and their tension play a huge role in how the game feels on court. After all, your strings are what actually make contact with the ball. Whether you are after more power, extreme spin, ultimate control, or a comfortable, arm-friendly feel, the right string setup makes a massive difference. In this guide, we explain everything about tennis strings and how to make the right choice for your game.

In this guide, we cover the following topics:

1. The different types of tennis strings
2. String gauge and its effect on your gamet
3. What string tension should you choose for your racket?
4. What other factors determine the ideal string setup?
5. Why should you restring your tennis racket regularly?
6. How often should you restring your racket?
7. Tennis strings and injuries: how to prevent tennis elbow
8. Frequently asked questions about tennis strings
9. Conclusion: this is how to choose the right tennis strings!

The different types of tennis strings

Before you can make the right choice, it helps to understand the different types of tennis strings available. We can divide them into four main categories: Monofilament, Multifilament, Natural Gut and Synthetic Gut.

Monofilament

Monofilament tennis strings are made from (co-)polyester. They consist of a single polyester core, often with chemical additives added to the polyester base to adjust the material's stiffness. This type of string is firmer than the other categories, giving it an edge in durability and control, even on full, powerful strokes from experienced players and professionals.

Advantages

• Excellent spin potential: (Co-)polyester strings are made from relatively smooth material compared to other string types. This creates more movement when the ball hits the string bed. Combined with the firmness of monofilament strings, this produces an effective "snap-back" effect: the strings quickly shoot back to their original position, adding extra rotation to the ball.
• Maximum control: Monofilament strings give players with hard, powerful strokes more control. The firm structure lets you swing through the ball with confidence. The harder material and high spin potential mean the ball is less likely to fly out.
• High durability: The composition of (co-)polyester holds up better against the hard impact of the ball than string types in other categories. This is a major reason monofilament strings are so popular among players who often break strings.

Disadvantages

• Less arm-friendly: The single (co-)polyester core makes monofilament strings less shock-absorbing. This means more of the ball's impact is transferred to your arm, adding extra strain on your wrist, forearm, elbow, and shoulder.
• Faster tension loss: All the movement, stretching, and snapping back of monofilament strings makes them lose their elasticity relatively quickly. The whole string bed loses tension and its characteristics change, making your strings feel dead or "gone" sooner.
• Lower power: With monofilament strings, you need to generate more power yourself to give the ball enough pace. Compared to multifilament, natural gut, or synthetic gut, they stretch and rebound less on short, slower swings. You only unlock the full potential of (co-)polyester strings once you are hitting full, fast strokes.

Multifilament

Multifilament tennis strings are made up of as many as several thousand ultra-thin microfibers, braided together into a single flexible core and finished with a protective coating, usually made from nylon (polyamide). These strings are designed to approximate the playing characteristics of natural gut, such as comfort, feel, and power, as closely as possible using synthetic materials.

Advantages

• Comfortable and arm-friendly: The structure of the many microfibers absorbs vibrations at ball impact extremely well. The flexible structure absorbs the impact and spreads it across the fibers, instead of transferring it directly to your arm. This significantly reduces the strain on your joints and muscles, making it an ideal choice for preventing or relieving injuries such as tennis elbow.
• High power: Multifilament strings are very elastic and offer a strong "trampoline effect". The string stretches easily on ball contact and springs back quickly. This means you get plenty of pace and depth on the ball, even with relatively little effort or a shorter swing.
• Good tension maintenance: Unlike monofilament strings, multifilament strings hold onto their tension and elasticity for a longer period. As a result, the string keeps feeling more consistent in terms of playability and comfort until it breaks or fully dries out.

Disadvantages

• Lower durability: Because of their microfiber construction and the constant friction between the mains and crosses under a fairly stiff coating, the string will eventually start to fray. For players who hit heavy topspin or who tend to break strings on their own, a multifilament string's lifespan is relatively short.
• Less control on fast, hard strokes: Because the string is so elastic, the ball tends to stay on the string bed slightly longer, and can fly off somewhat less predictably on very powerful, fast strokes. Players with a very fast swing may feel like they are losing control over the ball's trajectory as a result.
• Less spin potential: Multifilament strings have a weaker "snap-back" than monofilament strings. They move less freely against each other and snap back to their original position with less force, making it harder to add rotation to the ball.

Natural gut

Natural gut is the absolute classic, and still counts as the "gold standard" among tennis strings. These strings are made today from a natural byproduct of bovine intestines; sheep gut was used a lot in the earlier days of tennis as well. Despite all the technological advances in synthetic materials, the unique, elastic fiber structure of a natural gut string remains unmatched when it comes to feel, comfort, and tension maintenance.

Advantages

• Ultimate comfort and maximum vibration dampening: Natural gut offers the best shock absorption of any string type. Ball impact feels extremely soft, putting the smallest possible load on your arm, elbow, and shoulder. This makes it the most arm-friendly tennis string on the market.
• Superior tension maintenance: No synthetic string holds its tension as well as natural gut. It barely loses any tension over its entire lifespan and keeps its unique playing characteristics right up until the very last stroke.
• Exceptional feel and power: Natural gut's natural elasticity creates longer contact between your strings and the ball. This gives you an unmatched sense of control when placing delicate shots, while also delivering effortless power on full strokes.

Disadvantages

• High price: The production process for natural gut is highly complex, time-consuming, and labor-intensive. As a result, the price per set is considerably higher than synthetic alternatives.
• Sensitive to weather conditions: Because it is a natural product, the string reacts more strongly to moisture, rain, and large temperature swings. Moisture can damage the fibers, negatively affecting both lifespan and performance.
• Lower durability with heavy spin: For players with an extremely spin-heavy, powerful playing style, natural gut wears out faster due to the constant friction between the strings.

Synthetic gut

Synthetic gut is a nylon string built around a single solid, sturdy core, wrapped in one or more protective layers of thinner filaments. This category was originally developed as an affordable alternative to natural gut that lasts longer and holds up better against weather conditions. Today, synthetic gut serves as the most affordable option in the string market.

Advantages

• Accessible price: This type of string is the most affordable to buy, making it a solid budget option.
• Balanced playing characteristics: Synthetic gut offers an okay balance of comfort, control, durability, and power. It does not excel dramatically in any single area, but it is good enough for many players to rely on.
• Unaffected by weather conditions: The nylon material holds up excellently against moisture, cold weather, and temperature changes. That means you can play with confidence on court in any conditions.

Disadvantages

• No standout specialty: For players with very specific needs, synthetic gut falls short. It does not offer the extreme spin and control of monofilament, nor the ultimate comfort and power of multifilament or natural gut.
• Average lifespan: With intensive use and hard strokes, this string will break sooner than a firmer (co-)polyester string.

String gauge and its effect on your game

Tennis strings come in a range of different gauges, usually somewhere between 1.10 and 1.35 millimeters, with 1.25 mm being the most commonly used.

Slightly thinner strings: less than 1.25 mm

Thinner tennis strings offer more feel, spin, and power, since they stretch more easily. The trade-off is that they are more fragile and break sooner than thicker strings within the same category.

The most common string gauge: 1.25 mm

1.25 mm is an extremely popular string gauge. This thickness gives many players a healthy balance between enjoying a string's playing characteristics and its durability.

Slightly thicker strings

These strings, 1.30 mm or thicker, offer greater durability. Because they are thicker, they are harder to stretch and move less against each other. This makes spin and power less accessible, but gives you more control. They also break less easily than thinner strings within the same category.

What string tension should you choose for your racket?

The force used to pull the strings tight during stringing is expressed in kilograms (kg) or pounds (lbs). Just like the type of string you use, this tension has a major effect on how your strings perform. It directly influences power, control, spin potential, comfort, forgiveness, and durability!

The ideal tension for you depends heavily on a number of factors. Think of the type of string you use, which racket you play with, and which playing characteristics you are most after. Even the altitude you play at and weather conditions affect how your strings feel.

Preferences vary hugely, even among professional players. With so many factors at play, and everyone's sense of feel being different, figuring out what tension to string your racket at can be tricky. So here are a few guidelines to help you out:

The most common string tension

At Tennis Only, we string several thousand rackets every year. While some requests fall well outside the norm, we can say with confidence that the most common tension among our customers is 24 kg. We also found this seems to be a solid starting point for players who do not yet know their own preference, letting them find out whether they like the string or not, and whether they might want more power, control, spin, or forgiveness next time around.

What happens when you change the tension?

When you get your racket restrung, you can of course adjust the tension compared to your previous string job if you want to. If you do not stick with the same number of kilos (or pounds) as before, you have two options: go higher or go lower. This is usually done in whole or half kilos, though not always; many electronic stringing machines let you adjust in steps as small as 100 grams. How much these changes affect your strings' playing characteristics depends on where you are starting from, and how fresh or old your strings are also matters a great deal. But generally speaking, the following occurs:

Increasing tension

Increasing tension means the strings are pulled tighter in the racket head. As a result, it takes more force to make the strings move and stretch further. The less tennis strings move and stretch, the less they are forced to spring back to their original position. This means you will have to work harder yourself to add spin and power to the ball. At the same time, it lets you swing through the ball harder without it flying off your strings.

A higher tension means the strings move against each other less easily. This creates less friction, giving your strings a slightly longer lifespan. With fresh, lively strings, this also means more control on powerful strokes, but less comfort and less ease generating spin and power.

If you notice the ball leaving your strings in an uncontrolled way at, say, 23 kg (51 lbs), you could try bumping it up to 24 kg (53 lbs).

Decreasing tension

Decreasing tension means the strings sit looser in your racket head. This makes it easier for the ball's impact to move and stretch them. The more tennis strings stretch and move, the more they need to snap back sideways or upward to return to their original position. This means your strings generate spin and power more easily, even on slower or less powerful strokes. At the same time, it becomes harder to keep the ball under control on long, powerful strokes.

A lower tension results in more string movement. This means the strings rub against each other more often and more intensely, which can make them break sooner. On the plus side, with fresh, lively strings, this can boost the amount of spin and power you generate and the comfort you feel, but it can also mean less control over the ball's trajectory on long, powerful (flat) strokes.

If it is taking too much effort or energy to give the ball enough spin and pace at 24 kg (53 lbs), you could try dropping down to 23 kg (51 lbs).

What other factors determine the ideal string setup?

Beyond the general guidelines, there are a few more factors that help determine the ideal string setup for you:

String pattern

With an open string pattern, the strings sit farther apart. This gives them more room to move and spreads ball impact across fewer strings, giving you easier access to spin and power. Do you play with an open string pattern but want a bit more control on full strokes? Then it can help to use a higher tension and/or choose a firmer string.

Another consequence of an open string pattern is that strings are more fragile and break sooner. Do your strings break too quickly in a racket with an open pattern? Choose a firmer string or a thicker version of your current string. Unfortunately, this will cost you a bit of spin potential and power.

Is the string pattern in your racket denser instead, and are you looking for more spin, power, and feel? Then you could choose a thinner string. This often costs you some string life, though, since thinner strings are generally more fragile and can break sooner.

Head size

With larger racket heads, the strings tend to stretch and rebound more when you hit the ball. That is because the strings get less support from the frame across a larger surface area, letting them move more on ball impact. This creates extra power and a stronger trampoline effect. Do you play with a larger head size (over 100 sq in) and find that the ball flies off too unpredictably? A higher tension and/or a firmer string can help rein in that extra movement.

With a smaller racket head (under 100 sq in), it is the other way around. The strings sit more tightly packed within a smaller frame, so they naturally have less room to move. This gives you more control, but slightly less accessible power. Do you play with a smaller head size and want a bit more ease generating power or spin? A slightly lower tension and/or a more elastic string could work well for you.

String types and combinations

Beyond string pattern, head size, and injury sensitivity, the type of string you use naturally remains the foundation of your string setup. Torn between two categories or strings? Maybe the durability and spin of monofilament appeal to you, but you are also after the comfort of multifilament or natural gut? You do not necessarily have to pick just one.

Hybrid stringing

With hybrid stringing, you combine two different strings in a single racket: often a firm monofilament string in one direction for control and durability, paired with a softer multifilament or natural gut string in the other direction for extra comfort and feel. These days, though, hybrid setups are also made by combining two different monofilament strings increasingly often.

This way, you build a string setup that combines the strengths of multiple string types or strings, which also explains why this combination is so popular among professional tennis players. Which string you use in which direction also has a major impact on your string bed's playing characteristics.

The main strings mostly determine power, spin, and feel. The cross strings mainly provide stability, control, and comfort, and support how the mains perform. Together, they ultimately determine how the string bed behaves.

Not sure which combination best suits your game? Feel free to get in touch with our specialists for personal advice.

Tension based on string type

Not every string performs exactly the same at the same tension. Because a string's material and construction directly affect how stiff, elastic, or lively it feels, it makes sense to match your chosen tension to the type of string you are playing with.

Monofilament

Monofilament strings are already fairly stiff on their own and stretch less easily than other string types. Combine that with a high tension, and your strings can quickly start to feel harsh and transfer more vibration to your arm. That is why it is often recommended to string monofilament a touch lower than you would multifilament, natural gut, or synthetic gut. This helps offset the material's naturally stiff characteristics while keeping enough comfort and ease generating power and spin.

Multifilament

Multifilament strings are already fairly elastic and comfortable on their own. This means you can generally string them at your usual, average tension without any issues. Looking for a bit more control without giving up too much comfort? You can raise the tension on a multifilament string slightly, without immediately sacrificing its arm-friendly properties.

Natural gut

Because the natural gut holds onto its tension and liveliness exceptionally well, you can string it comfortably at the usual tension, or even slightly higher. This gives you extra control without sacrificing the unique, soft feel natural gut is known for.

Synthetic gut

Synthetic gut behaves as a balanced all-rounder, and you can pretty much always string it comfortably at your average, usual tension without needing to deviate much.

Tension in a hybrid string setup

Using two different strings in one setup? You can choose to string both at the same tension, but you can also let the tension of your mains and crosses differ. For example, string a stiff monofilament main slightly lower than usual, combined with a multifilament or natural gut cross at a normal tension. This way, you combine the control and durability of monofilament with extra comfort, without sacrificing too much overall feel.

This lets you fine-tune not just the type of string, but also the tension per string, to exactly what you are looking for in your setup.

Why should you restring your tennis racket regularly?

You might think: "My strings aren't broken yet, so I don't need to replace them." This is a common mistake. A string loses its properties and advantages long before it actually breaks. In fact, your strings can start working against your enjoyment, performance, and comfort if you do not replace them in time. The causes behind this include:

Tension loss

The moment a racket comes off the stringing machine, the strings start losing tension. Even if you leave the racket in a closet or neatly packed in your tennis bag, the tension drops. Once you start playing with it, this happens even faster, as the strings move on every ball impact! As tension loss builds up, the string's liveliness drops and its playing characteristics change, usually for the worse.

Loss of elasticity

During play, it is completely normal for tennis strings to stretch and rebound on ball impact before the ball leaves the strings. Over time, and the more you play, your strings lose that rebound. Once the elasticity is gone, the string has reached the end of its life. You will notice this through balls flying off unpredictably, a dull sound at impact, and more vibration in your arm.

Drying out

One category of strings dries out over time. Multifilament strings are made from synthetic materials, which is exactly why they feel extra soft, elastic, and comfortable, especially right after stringing, when your setup is still fresh. From that point on, the drying-out process begins. A string setup like this will start to creak after a while and stop snapping back to its original position. The soft, comfortable properties fade, and the string becomes noticeably stiffer instead. As a result, characteristics like power, feel, and comfort deteriorate significantly, and the string starts working against you. You will need to hit harder to give the ball enough pace, and the impact of vibrations on your arm gets worse.

How often should you restring your racket?

This depends heavily on your playing level and frequency, which strings you use, and how you store your racket(s) and strings. As a general rule: the higher your level and the more often you play, the more often you will need to restring your racket(s). Simply because the ball moves the strings more often and more intensely. As a result, tension loss and loss of elasticity also build up faster.

If you hit harder and with more spin, your strings are also more likely to break during play. Of course, they will need replacing right away before you can get back on court!

Not (yet) a string breaker? Then we recommend restringing your racket at least as many times per year as you play per week on average, with a minimum of twice a year. Do you play about 3 times a week, for example? Then get your racket restrung at least every 4 months to counter the negative effects of tension loss, loss of elasticity, and/or drying out.

Tennis strings and injuries: how to prevent tennis elbow

Choosing the wrong string and not replacing your strings in time are two common (contributing) causes of tennis elbow. To reduce the risk of painful injuries, it is important to understand what the possible culprits are, and how to counter them.

Possible culprits

Culprits that could lead to tennis elbow or other painful wrist, arm, elbow, or shoulder injuries include: a string that is too stiff, a tension that is too high, not replacing your strings in time, an unsuitable racket, or a combination of these.

A string that is too stiff

A stiff tennis string absorbs vibrations at ball impact less effectively. As a result, those vibrations get passed straight through to your arm. If a string is too stiff for you, you will notice the unpleasant effects through extra strain on your wrist, arm, elbow, or shoulder.

Tension that is too high

A high tension means the strings in your racket head are pulled tight. This means a lot of mass is needed to stretch them at ball impact. When strings barely stretch, they barely spring back either. This means you have to work harder to give the ball enough pace.

If the tension is too high for you, you will tend to compensate by putting more force into your strokes. This often comes at the expense of your technique and a relaxed arm. Forcing your strokes and gripping tightly can put too much strain on your muscles, which can lead to painful injuries.

Not replacing your strings in time

Not replacing your strings in time can affect your arm negatively in a number of ways.

▶ Setups with monofilament strings

With monofilament strings, tension, elasticity, and liveliness drop off to the point where they no longer help absorb impact, since they no longer stretch and snap back quickly and powerfully the way they did at first. This means vibrations and ball impact get passed through to your arm more, which then has to absorb more strain.

▶ Setups with multifilament strings

With multifilament strings, they will dry out. If you do not replace them in time, you will be playing with strings that are supposed to be elastic and comfortable, but have completely lost those positive properties. Old multifilament strings become very stiff and lose their elasticity. As a result, vibrations are no longer absorbed by the many soft fibers in the string's core, and instead get sent straight to your arm. On top of that, you will need to put in extra effort to give the ball enough pace, which intensifies the impact on your arm even further.

An unsuitable racket

Besides your strings, using a racket that does not suit you is also a potential cause of painful arm injuries.

▶ A racket that is too heavy

Is your racket too heavy? Then it takes too much effort to make a smooth, full swing. This makes it hard to keep your arm relaxed and makes timing the ball correctly extra difficult. With a tense arm and mistimed contact, you run a higher risk of overloading your arm muscles, which can lead to nagging aches or even injuries.

▶ A racket that is too light

Is your racket too light? Then you lack the mass and stability to easily generate enough power, and you will tend to use more arm strength to give the ball depth. Forcing your arm muscles at ball impact can lead to overuse and even injuries.

▶ The wrong type of racket

The type of racket also partly determines how much comfort you experience at ball impact, though this naturally varies by model. Do you play with a stiff, power-oriented frame? Then it will generally transfer quite a lot of vibration from ball impact to your arm.

Do you use a flexible, control-oriented frame instead? That can help absorb vibrations, but you will need to generate enough pace on the ball yourself. If your technique cannot make up for that, it demands more physical strength, which raises the risk of overuse and injury.

Possible solutions

Fortunately, for the various potential causes of tennis elbow or other arm injuries, there are also ways to minimize their negative impact as much as possible. These relate to your string, tension, restringing frequency, and racket.

Do you have a history of arm issues or sensitive joints? Then factor this in extra carefully when choosing both your string and your tension: a softer string like multifilament or natural gut, combined with a slightly lower tension, generally offers more protection for your arm, elbow, and shoulder.

Pay attention to string stiffness

Are you going with monofilament or multifilament? And where within these categories does the right stiffness for you sit? You can often tell how stiff a string is, and which players it suits, from its product information. No time to research it, or genuinely no idea? Then definitely ask an expert for advice.

Find the right tension for you

To prevent injuries, it is often wise not to string your racket at too high a tension. Are you happy with the string you are using, but looking for just a bit more comfort or ease generating power or spin? Then try a slightly lower tension.

Get your racket restrung on time

Getting your racket restrung on time is the best way to avoid the downsides of old, dead strings. No matter which string you use, it is wise to replace it regularly. Not sure how often you need it? We have discussed the frequency in an earlier chapter.

Use a racket that suits you

It is not just your strings that matter; your racket does too. The right racket weight and a frame type that suits your game are already two steps in the right direction. Want to learn more about which tennis racket suits you? Check out our tennis racket guide.

Frequently asked questions about tennis strings and stringing

In our many years of experience on and off the court, we have answered almost every question about tennis strings and stringing you can think of. To make it easy, we have listed some of the frequently asked questions and our answers. Has your question not been answered yet? Feel free to contact us!

Conclusion: This is how to choose the right tennis shoes!

Let us go over the most important points again:

• Choose the string type that suits your game and your body. After maximum control, spin, and durability? Go for monofilament. Want comfort and effortless power instead? Choose multifilament. After the best of both worlds and have a bigger budget? Consider a natural gut or a hybrid setup. Looking for a reliable all-rounder at an accessible price? Then synthetic gut is an option for you.
• Pay attention to string gauge. Thinner strings (under 1.25 mm) offer more feel, spin, and power, but are more fragile. Thicker strings (1.30 mm or more) last longer, but offer slightly less playability. 1.25 mm is the sweet spot for many players.
• Determine the right tension for you. A higher tension offers more control and durability; a lower tension gives you more power, spin, and comfort. Also factor in your string pattern, head size, and the type of string you use. 24 kg (53 lbs) is a commonly used starting point if you do not yet know your preference.
• Replace your strings on time, even if they have not broken yet. Tension loss, loss of elasticity, and drying out all wear down your strings' playing characteristics long before a string actually snaps.
• Figure out how often you should restring your racket. The higher your level and playing frequency, the more often you will need a fresh string job. Rule of thumb: restring at least as many times a year as you play per week on average, with a minimum of twice a year.
• Prevent tennis elbow. A string that is too stiff, a tension that is too high, strings you have held onto for too long, or an unsuitable racket can all contribute to arm issues. Prone to this? Choose a softer string, a lower tension, and a racket that suits you.

Still not sure? Feel free to ask our specialists for advice. We are happy to help you put together the string setup that best suits your game.