Nerdle is a math Wordle - Find Hidden Equation Puzzle Game
Aside from the obvious arithmetic variation, Plusle as well as Nerdle requires players to fill eight blocks compared to Wordle’s five allotted spaces. While five of these Plusle blocks usually are filled by numbers, the other three blocks are filled with mathematical symbols that are used to complete the equation.
Again, just like Wordle, Nerdle and the vast majority of games like those, Plusle is entirely free to play. And unlike Wordle, which was recently snapped up by The New York Times, there's no suggestion that Plusle will ever become a paid game in any way.