Binary and Hexadecimal Explained: Converting Number Bases
How place value works in binary and hexadecimal, and how to convert between decimal, binary and hex step by step.
Solve → Understand → Practise
Maths, worked out step by step
103 free calculators that show the answer, every step, the rule behind it, and how the answer was checked. Free to use. No sign-up needed.
Popular calculators
All 103 calculators →Percentage Calculator
Free percentage calculator: find X% of Y, what percent one number is of another, the whole from a part, or add and remove a percentage.
Fraction Calculator
Free fraction calculator for adding, subtracting, multiplying and dividing fractions and mixed numbers.
Quadratic Equation Solver
Solve ax² + bx + c = 0 with the quadratic formula.
Square Root Calculator
Find the square root of any number, simplified exactly (like √50 = 5√2) with the decimal value.
Standard Deviation Calculator
Calculate the standard deviation and variance of a data set, for a sample or a population, with the deviations table and every step shown.
Age Calculator
Calculate your exact age in years, months and days from your date of birth, plus total days lived and a countdown to your next birthday.
How it works
- 1
Type your numbers
Enter the values, or tap an example to see how a calculator works.
- 2
See every step
Every step names the rule or formula used, so you know why it works.
- 3
Trust the answer
Each answer is checked a second way, such as substituting it back in, before it is shown.
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