The James Smith Calculator is a free online tool that helps you calculate your daily calorie needs and macronutrient targets for fat loss, muscle gain, or weight maintenance. It uses your personal stats—height, weight, age, gender, activity level, and goals—to provide accurate, personalized recommendations.
The calculator is backed by James Smith, a leading UK-based personal trainer and fitness coach. James is the founder of the James Smith Academy, an online fitness program that has helped thousands reach their goals, and the author of three bestselling books: Not a Diet Book, How to Be Confident, and Not a Life Coach.
James focuses on realistic, sustainable fitness strategies and empowers people to achieve their goals without gimmicks, crash diets, or confusion. The calculator reflects his expertise and practical approach, giving you a tool that’s simple to use, reliable, and actionable.
Our mission is to make science-based fitness guidance accessible to everyone, helping you take control of your nutrition and reach your full potential.