The ITF's global rating system designed to give every tennis player worldwide a comparable number for singles and for doubles. Here's what you need to know.
The World Tennis Number (WTN) is the International Tennis Federation's (ITF) global rating system. Its goal is ambitious: give every tennis player on the planet a single number that allows them to be compared regardless of country, league, or rating system.
WTN uses a 40 to 1 scale where lower is better (the opposite direction of UTR). A complete beginner starts at 40, while a top professional would be close to 1. The system is free to access and updates weekly, every Wednesday, based on match results from ITF-affiliated events.
Adoption in the US recreational market is still in its early stages. Most American players are more familiar with NTRP and UTR. However, WTN has strong backing from the ITF and is gaining traction internationally, especially in countries where neither NTRP nor UTR has a dominant presence.
Unlike NTRP (2.0–7.0, higher = better) and UTR (1.0–16.0, higher = better), WTN runs in reverse. A WTN of 15 is an expert-level player. A WTN of 35 is a beginner. This is the most common source of confusion when comparing systems.
How the reverse scale maps to player ability levels.
| WTN Range | Level | NTRP Equivalent | Description |
|---|---|---|---|
| 39 – 40 | Beginner | 2.0 | Just starting. Learning fundamentals. |
| 34 – 39 | Adv. Beginner | 2.5 – 3.0 | Developing consistency. Basic rallying and serve. |
| 25 – 34 | Intermediate | 3.5 – 4.0 | Consistent strokes with variety. Competitive league player. |
| 15 – 25 | Advanced | 4.5 – 5.0 | Mastering power, spin, and strategy. Strong all-court game. |
| 1 – 15 | Elite / Pro | 5.5 – 6.0+ | National/international competitors. Touring professionals. |
Two numbers, not one, and a weekly update. Here is the current system, after the August 2026 changes.
WTN gives you one number for singles and a separate number for doubles. They are not interchangeable, and they often land in different ranges for the same player. A singles rating is based only on singles matches, and a doubles rating only on doubles matches. Whenever I mention a WTN on this page, I mean one of the two, never a blended number.
Before each match, the algorithm predicts an outcome from both players' ratings. After the match, your rating moves by the gap between the prediction and the actual result. Beating a much better player moves you a lot. Losing to a much better player moves you little. Winning a match you were expected to win comfortably can leave you flat, or even worse, if the score was closer than expected.
Sets dominate the calculation, and since August 2026 the games inside each set count too. A 6-0 set moves you more than a 6-4 set, and a 7-6, 7-6 win no longer counts the same as a 6-0, 6-0 win. Longer sets carry more weight than short sets, and a match tiebreak carries less weight than a full set.
Recent results weigh more than old ones, and since August 2026 your rating uses a rolling three-year window. Older results stay in your match history but stop influencing your rating, with their influence fading gradually rather than dropping off a cliff.
Defaults are not factored into WTN. Retirements and incomplete matches use whatever score data is available.
More matches, more opponents, and more recent matches mean higher confidence and smaller swings. A blue check means high confidence. A grey check means low confidence, and a low-confidence rating swings more from the same results. As a guideline, confidence falls if you go inactive for two months, and the highest confidence level sits at 30 or more recorded matches per year.
Since August 2026 there are two small adjustments. One accounts for natural player development, mainly for juniors, so junior ratings stay aligned with adult levels. The other is a small, gradual adjustment if you have not competed for over a year. When you return, your confidence is lower, so the algorithm reacts more strongly to your new results.
Since August 2026 the doubles algorithm no longer considers your partner's rating, to better reflect your own performance against your opponents. Gender doubles and mixed doubles both feed your one doubles WTN.
WTN updates weekly, every Wednesday, not daily and not in real time. A match you play on Saturday will not move your number until the Wednesday update.
The USTA states there is no direct one-to-one comparison between NTRP and WTN. The two systems use different algorithms and different match sets, WTN has separate singles and doubles numbers against a single NTRP, mixed doubles is handled differently, and WTN publishes weekly while NTRP publishes annually. That is why this guide shows ranges, and why I do not publish a single-number WTN converter.
The ITF has repositioned whole groups of players three times since 2023. Each change moved many players' numbers without them playing a match.
July 2023: Age-band redistribution. Cohorts were repositioned to make fuller use of the 1 to 40 scale and to align populations worldwide. Masters players (30 and over) generally moved toward 40, juniors aged 17 to 18 moved toward 1, and adults aged 18 to 29 saw mostly minor changes.
September 2024: Junior initialisation fix and faster convergence. Juniors had been started too high, so their starting point was lowered and ratings moved toward true skill faster from the first few matches. Losses to a superior player also got smaller, while beating a substantially better player still gave a sharp improvement.
August 2026: The current system. Rolling three-year window, game-level scoring inside sets, a small development adjustment (mainly juniors), a small gradual adjustment for more than a year of inactivity, and doubles no longer using the partner rating.
If your number jumped on one of those dates, that is the likely explanation, not a data error. Any conversion table fitted to WTNs from before August 2026 is stale.
How the three systems compare on the factors that matter most to players.
| Factor | WTN | NTRP | UTR |
|---|---|---|---|
| Scale | 40 → 1 (lower = better) | 2.0 → 7.0 (higher = better) | 1.0 → 16+ (higher = better) |
| Update Frequency | Weekly, every Wednesday | Once per year | After every match |
| Governing Body | ITF (International) | USTA (US only) | Universal Tennis (Private) |
| Cost | Free | Free (with USTA membership) | $10-12/mo for full access |
| Score Margin | Yes, factored in | No, win/loss only | Yes, heavily weighted |
| US Adoption | Early / growing | Dominant standard | Widely used, growing fast |
You can look up your WTN on the ITF's official World Tennis Number website (worldtennisnumber.com). You'll need to create an IPIN (International Player Identification Number) account if you don't have one. If you've played in ITF-affiliated events or your national federation reports to the ITF, you should have a WTN.
The USTA is affiliated with the ITF, and some USTA match results do feed into the WTN system. However, not all local league matches may be reported. Tournament results and higher-level USTA events are more likely to be included. Check the ITF site to see which of your matches have been captured.
The ITF chose a scale where lower numbers represent better players, similar to golf handicaps. The thinking is that this intuitively represents "fewer weaknesses" or "closer to perfection." While it can be confusing when comparing to NTRP or UTR, the reverse scale is consistent within the WTN system once you're familiar with it.
It's unlikely in the near term. NTRP is deeply embedded in USTA league infrastructure, and hundreds of thousands of players use it for league registration. WTN is more likely to coexist as an additional reference point. However, if the ITF pushes hard for global standardization, there could be pressure on national federations to adopt WTN as a primary system over time.
WTN updates more frequently than NTRP and considers score margins, making it potentially more reflective of current ability. However, its accuracy for US recreational players depends heavily on how many of your matches are reported to the ITF. If most of your play is in local USTA leagues that aren't fully captured, your WTN may be less representative than your NTRP.
The structural reasons no reliable conversion exists. Data, not opinion.
WTN gives you two numbers: one for singles, one for doubles. NTRP gives you one. A player's WTN Singles and WTN Doubles can land in completely different ranges, which makes any "WTN to NTRP" conversion fundamentally ambiguous. Most USTA league players compete primarily in doubles, but their WTN Singles rating is often the more visible number.
Schmidt Computer Ratings found that a single NTRP level can span 10 to 30 WTN points. On a 40-point scale, that means a WTN of 28 could be an NTRP 3.5 or an NTRP 4.0, depending on the player. A "conversion" with that kind of range is not a conversion. It's a coin flip with a decimal point.
The USTA explicitly states there is no direct one-to-one comparison between NTRP and WTN. That is not a gap in their documentation. It's a deliberate statement from the governing body that built the NTRP system. They're telling you the two scales don't line up.
A verified USTA 4.0C player entered his WTN Singles (28.09) and got back an NTRP equivalent of 3.0. A full level off. His UTR of 6.3 correctly returned 4.1. A second player at the 3.5C level showed the same pattern: UTR tracked accurately, WTN did not. These are not edge cases. The mismatch is structural and no amount of recalibration will resolve it.
This is why MyTennisRatings removed WTN from the Rating Translator. I only publish conversions I can stand behind. The full transparency post has the complete story behind the decision.
You might also find useful: Rating Translator · UTR Explained · How the Models Work