🏆 The short version
- Leading trio: Head Lynx Tour (16.3/20), Solinco Confidential (15.6) and Solinco Mach-10 (15.5). The gaps sit close to the margin of error: a trio, not a podium.
- Top-ranked is not softest. Confidential, 2nd, is one of the stiffest of the group (245 lb/in). Luxilon 4G, 8th, is the stiffest (286.9 lb/in).
- For the arm: Toroline O-Toro (165.7 lb/in) is by far the softest poly of the 18, and it ranks 4th. The next one, Yonex Poly Tour Rev (205 lb/in), is 14th.
- Tension does not make up for the string. In the same frame, 4 kg (about 9 lb) less removes 2 RCS points; switching from 4G to O-Toro removes 14.
"What is the best poly?" is the question pro shops hear most, and the most poorly framed. An overall ranking rewards a complete string for a player who hits hard. It says nothing about what that string will do to your elbow. So we took a testers' ranking and re-read it through the one criterion those tests do not score directly: the firmness of the setup.
🔎 1. Where this ranking comes from, and what it is worth
The starting point is a synthesis of specialist tester reviews, consolidated on October 9, 2026: three testers who publish string reviews, cross-checked so that only strings assessed by at least two of them are kept. Each string gets a score out of 20 on ten criteria — control, spin, power, feel, comfort, consistency, tension maintenance, durability, value for money, versatility — then an average and a tier, from S to D.
Three things to know before reading the table:
- It is an assessment, not a measurement. The testers do not score these ten criteria separately; the synthesis rebuilds them from their reviews. Its margin of error is estimated at about 0.5 point on an average. Two strings less than half a point apart are tied.
- The testers are not independent. They know each other, and some sell or co-brand strings from brands ranked here. We say so because it matters, without claiming to know which way it cuts.
- We only rank what we have documented. 18 of the strings assessed have a product page in our catalogue, with a stiffness value. The others are listed further down, without a score.
🏆 2. The ranking of the 18 polyesters
Sorted by the testers' average. Stiffness comes from our product pages, in lb/in. The RCS index is computed with the site's formula for one shared example — a racquet with an RA of 65, strung at 22 kg (48.5 lb) — to compare strings with everything else held equal.
| # | String | Testers /20 | Tier | Stiffness (lb/in) | RCS (example) |
|---|---|---|---|---|---|
| 1 | Head Lynx Tour † | 16.3 | S | 228.6 | 31 |
| 2 | Solinco Confidential | 15.6 | A | 245 | 33 |
| 3 | Solinco Mach-10 † | 15.5 | A | 222.3 | 31 |
| 4 | Toroline O-Toro † | 15.3 | A | 165.7 | 24 |
| 5 | Head Hawk Touch | 14.8 | B | 215 | 30 |
| 5 | ReString Zero | 14.8 | B | 210 | 29 |
| 7 | Solinco Hyper-G † | 14.6 | B | 218.3 | 30 |
| 8 | Luxilon 4G † | 14.5 | B | 286.9 | 38 |
| 9 | Solinco Tour Bite | 14.4 | B | 255 | 34 |
| 10 | Signum Pro X-Perience † | 13.6 | C | 224.6 | 31 |
| 11 | Babolat RPM Rough | 13.3 | C | 235 | 32 |
| 11 | Völkl Cyclone | 13.3 | C | 215 | 30 |
| 13 | Luxilon ALU Power | 13.2 | C | 230 | 31 |
| 14 | Yonex Poly Tour Rev | 13.0 | C | 205 | 29 |
| 15 | Babolat RPM Blast | 12.4 | D | 240 | 32 |
| 16 | Yonex Poly Tour Pro | 12.3 | D | 220 | 30 |
| 17 | Babolat RPM Team † | 11.9 | D | 280.6 | 37 |
| 18 | Weiss Cannon Ultra Cable | 11.6 | D | 250 | 34 |
How to read it: tiers S ≥ 16, A 15 to 15.99, B 14 to 14.99, C 13 to 13.99, D below 13. RCS: firmness index of the setup, from "very comfortable" (below 20) to "very firm" (35 and above, tennis elbow risk). Every string is in our strings catalogue.
† Stiffness aligned on a measurement by the Tennis Warehouse University (TWU) lab: when the product page groups several gauges, it is the one for the stiffest gauge TWU measured. The other values come from our product pages: they are not aligned on a lab measurement and may differ from one, in either direction.
What the table shows first: the top is tight. From 3rd to 9th, the averages fit within 1.1 points; several pairs are inside the margin of error. Then, ranking and stiffness do not travel together: the softest of the 18, Toroline O-Toro, is 4th, and the stiffest, Luxilon 4G, is 8th, ahead of softer strings. Finally, tier D brings together RPM Blast, which the testers judge outdated and harsh on the arm as it ages, and three strings with a more extreme profile.
🎯 3. The best for what you are after
An average blends opposite qualities. Here are the best of the 18 on four criteria, from the scores out of 10 on our product pages (they combine our earlier ratings with the tester reviews).
| You want… | Best rated (product page score /10) | Watch out |
|---|---|---|
| Control | Luxilon 4G and Solinco Tour Bite (10), Solinco Confidential and Luxilon ALU Power (9.8), Head Lynx Tour (9.5) | The first four sit at 31 to 38 RCS in our example |
| Spin | Toroline O-Toro and Babolat RPM Rough (10), Weiss Cannon Ultra Cable (9.8), Solinco Tour Bite (9.7) | O-Toro is the only soft string in this group |
| Comfort | Solinco Mach-10 (8.8), Yonex Poly Tour Pro (8.6), Toroline O-Toro (8.1) | Poly Tour Pro is rated comfortable, but its sheet lists 220 lb/in, a value that is not measured (see § 4) |
| Durability | Solinco Confidential and ReString Zero (10), Luxilon 4G (9.8), Head Lynx Tour (9.3) | A string that lasts also keeps its firmness for a long time |
The most complete: Head Lynx Tour
Top of the ranking, tier S: it is the only string praised by all three testers. Control (9.5), versatility (9.5) and durability (9.3) on its product page, for a stiffness of 228.6 lb/in, just below the average of the 18 (230.4 lb/in). The default pick for a player with no arm issue.
The playability-comfort compromise: Solinco Mach-10
3rd, and the best rated of the 18 for comfort (8.8) and power (8.7), with a stiffness of 222.3 lb/in, the 8th lowest of the 18. For a player who wants a poly without giving up comfort, this is one of the first to try, as long as you check your setup's index (31 in our example).
The softest: Toroline O-Toro
4th, and by far the least stiff of our selection: 165.7 lb/in, nearly 40 lb/in below the next one, Yonex Poly Tour Rev (205 lb/in). Top spin score on its product page. Its durability (7.9) sits near the bottom of the group.
Control at a cost to the arm: Solinco Confidential, Luxilon 4G
Two remarkably stable strings — tension maintenance and durability among the best — and two of the stiffest: 245 and 286.9 lb/in. They are made for arms that can take it. 4G reaches 38 in our example, beyond the RCS "very firm" threshold (35).
🩺 4. Your arm first: what the RCS index says
The site's RCS combines frame stiffness, string stiffness and tension into one firmness index for the setup. It is built for one question: does this setup put your elbow at risk? Applied to the 18 polys in the same frame (RA 65, 22 kg), it runs from 24 to 38. Three takeaways.
The string weighs more than the tension
In the site's formula, 1 kg (2.2 lb) of tension is worth half an index point; 10 lb/in of string stiffness is worth a little over one. In the same frame, dropping Luxilon 4G from 22 to 18 kg (48.5 to 39.7 lb) takes the index from 38 to 36. Replacing 4G with Toroline O-Toro at 22 kg takes it from 38 to 24. If your arm complains, changing string is the main lever; lowering tension is only the second.
The frame matters too
The same 4G at 22 kg climbs to 39 in a frame with an RA of 70, and Tour Bite to 36. A stiff poly in a stiff frame stacks two firmnesses: that is the combination the configurator flags.
"Comfortable" for testers is not "soft" on the bench
Yonex Poly Tour Pro is the 2nd best rated for comfort (8.6), yet it is only the 7th softest of the 18: its stiffness (220 lb/in) is the median of the catalogue's 102 polyesters. Feel at impact and stiffness do not say the same thing. For a sensitive arm, look at stiffness first: it is what the RCS index uses.
⚠️ Sensitive arm or history of tennis elbow
No polyester ranking is a recommendation for you. Even the softest of the 18 is still a monofilament; a multifilament or natural gut is generally more prudent, as our guide polyester vs multifilament explains. If you stay with poly, take the softest one you are willing to play, in a flexible frame, and check your setup's index before buying.
Pain that persists is a matter for a doctor, not for a string.
The figures above are for a hypothetical frame. Yours depends on your racquet and your tension: the configurator computes the RCS index of your exact setup and shows a warning when it becomes risky for the arm.
🧾 5. The missing strings, and why
The synthesis assesses 33 strings. Fifteen do not yet have a product page in our catalogue — among them Grapplesnake Tour M8, Solinco Confidential Soft, Toroline Caviar, Pure Rush, Grapplesnake Tour Sniper, Solinco Hyper-G Round, Dunlop Explosive Tour and Yonex Poly Tour Force. Some rank very well.
We do not rank them for a simple reason: without a product page we have no verified stiffness, so no RCS index, so nothing to say about your arm. A string missing from this table is not a bad string; it is one we have not documented yet.
❓ FAQ — best polyester tennis strings 2026
What is the best polyester tennis string in 2026?
Among the 18 polyesters in our catalogue covered by the synthesis, Head Lynx Tour comes first (16.3 out of 20), ahead of Solinco Confidential (15.6) and Solinco Mach-10 (15.5). The gaps are close to the margin of error, about 0.5 point: a leading trio rather than a single winner.
Which polyester string should I pick with a sensitive arm?
The softest one you are willing to play, in a flexible frame. In our catalogue, Toroline O-Toro (165.7 lb/in) is by far the least stiff of the 18, ahead of Yonex Poly Tour Rev (205 lb/in). With a history of tennis elbow, a multifilament or natural gut generally remains a more prudent choice than a polyester, whatever its ranking.
Is lowering the tension enough to make a stiff polyester comfortable?
Not according to the site's RCS index: 4 kg (about 9 lb) less lowers the index by 2 points, while switching from Luxilon 4G (286.9 lb/in) to Toroline O-Toro (165.7 lb/in) lowers it by 14 points in the same frame. The string choice matters far more than the tension.