Jake wins unexpectedly in straight sets vs Brian who is better rated. Jake’s rating improves and Brian’s worsens.
How the WTN Works
The ITF World Tennis Number (WTN) is a modern, global rating system that makes it easy for players of all ages and abilities to measure their level and find evenly-matched opponents.
Unlike traditional rankings, which are based on tournament results, the WTN is a rating which focuses on your actual performance in matches. Whether you’re competing in international events or playing at your local club, every result submitted counts.
Your Global Scale
- The WTN runs on a scale from 40 to 1
- A separate rating for Singles and Doubles
- 40 is closer to beginner, and 1 represents the level of the world’s current best professional player
- Everyone has a rating – juniors, adults, seniors, casual players and pros
How matches impact my WTN
The WTN algorithm adjusts ratings based on match outcomes, rewarding surprising victories and penalising unexpected losses.
Jake loses 2–1 to Claire with a similar rating. Both ratings remain stable as the outcome was anticipated.
Lina beats Brian 2-1, but since she was expected to win, Brian is rewarded for taking a set while Lina is penalised.
Lina then suffers a surprise straight-sets loss to Claire, worsening her WTN as Claire’s improves significantly.
How It’s Calculated
The WTN algorithm is updated every Wednesday and is based on:
01 Whether you win or lose
Every match you play in eligible competition contributes to your WTN.
02 Your opponent level
How you perform against players of different abilities is a key factor. The better the opponent you beat, the more your rating will improve.
03 How close the match was
The algorithm takes into account each set as its own result even if you do not win the overall match.
04 Recency of your matches
Recent match results are given more weight over older ones, ensuring that current performance levels are reflected.
05 Confidence Level
The more confident we are in your rating, the more stable your rating becomes and is less volatile to unexpected results.
Why It Matters
Competitive Matches
Find opponents of a similar standard using the Game zONe, wherever you are in the world
Track Your Progress
See how your game develops over time with regular updates to your WTN and your rating history chart
Connect Globally
Be part of a worldwide community of tennis players, all measured on the same scale
Your WTN, Your Game
Whether you’re starting out, competing locally, or aiming for the top, the WTN is your guide to better, more enjoyable tennis.