What is the World Tennis Number—and why is it changing how tennis measures skill worldwide?

In this episode, we break down the World Tennis Number (WTN), the global rating system developed by the International Tennis Federation (ITF) to create a single, consistent measure of playing ability across all levels of the sport.

Using a scale from 40 (beginner) to 1 (elite professional), WTN evaluates match results at the set level and updates weekly to track progress and predict match outcomes. We explain how the algorithm works, what the Confidence Level really means, and how tools like Game zONe and Win Likelihood help players find competitive, well-matched opponents.

You’ll also learn how features such as head-to-head comparisons, personal watchlists, and the ability to record casual match scores fit into the broader WTN ecosystem—and why organizations like the USTA are adopting WTN for tournaments, player development, and college recruiting.

Whether you’re a player, coach, parent, or tennis administrator, this episode gives you a clear, practical understanding of the system shaping the future of competitive tennis.