NumWhiz

NumWhiz is a provider of free online calculators, web tools, puzzles, quizzes, and games, designed to make everyday calculations quick and accessible. Its tools require no signup or downloads, and calculations run in the user’s browser so personal inputs remain on the device. The site says it supports its services through clearly labeled advertising rather than selling user data.

NumWhiz offers calculators for personal finance, including salary-to-hourly pay conversions, compound interest, savings goals, loans, mortgages, rent-versus-buy decisions, debt payoff, Coast FIRE, and student loans. Other tools help users plan holiday spending, price pottery and clothing alterations, and estimate mobile dog-grooming business profitability. For everyday needs, the site includes GPA and calorie calculators.

Beyond calculators, NumWhiz features daily puzzles such as Sudoku and other logic games, money quizzes, and children’s games covering multiplication, time, counting money, and riddles. The brand describes its calculations as estimates and notes that they are not financial advice.