The ITF's global rating system designed to give every tennis player worldwide a single, comparable number. 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 regularly 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. |
The factors behind your World Tennis Number.
Your WTN is primarily based on match outcomes from ITF-affiliated events, including national federation leagues and tournaments. Each result adjusts your number.
The ITF uses a proprietary algorithm that considers opponent strength, score margin, and match context. It shares some principles with UTR but is independently developed.
WTN pulls data from national federations worldwide. If your national federation reports match results to the ITF, those matches feed into your WTN calculation.
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 | Regular (after matches) | 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