ChatCalculator

ChatCalculator adds a simple and easy-to-use calculator directly to Minecraft. With the /calc command, you can perform quick calculations without leaving the game or using an external calculator. You can add, subtract, multiply, and divide numbers, with support for large values using long numbers. When dividing, ChatCalculator also shows the remainder, making it useful for both simple calculations and larger numbers. The mod is designed to be lightweight, straightforward, and easy to use, so you can quickly calculate something whenever you need it while playing Minecraft.
Avaible on Curseforge too!