Math tools
13 toolsPercentages, tips, loan payments, compound interest, aspect ratios, fractions, and unit conversions, with the edge cases handled. Type your numbers and get the answer without building a spreadsheet for a thirty-second question.
Like everything on loot.tools, these run entirely in your browser. Free, no account, and nothing you enter leaves the tab.
Which one do you need?
The money questions come first, since that's usually why people are here. Percentage Calculator covers every phrasing of a percentage problem: what is 15% of X, X is what percent of Y, and percent change. Tip Calculator settles a restaurant bill and splits it, Loan Calculator turns a rate and a term into a monthly payment, and Compound Interest Calculator shows what a balance grows into over the years.
For working with the numbers themselves, Math Expression Evaluator evaluates a whole expression with parentheses and functions, so you don't have to chain steps on a phone calculator. Fraction Calculator does exact fraction arithmetic without rounding through decimals, Statistics Calculator returns the mean, median, mode, and spread of a pasted list, and Random Number Generator draws whole numbers in a range, with repeats or without.
The converters round the group out. Unit Converter moves between units of length, mass, temperature, speed, data, and more. Aspect Ratio Calculator keeps width and height in proportion when one of them changes. BMI Calculator, Roman Numeral Converter, and Number to Words Converter each answer exactly the question their names ask.