OmniCalcsMath Calculators
Free math calculators for percentages, fractions, statistics, probability and everyday math.
Percentage Calculator
Three modes: percent of, percent is, change.
Fraction Calculator
Add, subtract, multiply and divide fractions.
Decimal-Fraction-Percent
Convert between decimal, fraction and percent.
Scientific Calculator
Full scientific calculator with power functions.
Ratio Calculator
Solve a:b = c:d and simplify ratios.
Average Calculator
Mean, median, mode, range and more.
Probability Calculator
Single event and repeated-trial odds.
Statistics Calculator
Full descriptive stats for any dataset.
Exponent Calculator
Power, square and cube calculations.
Square Root Calculator
Roots of any degree with quick results.
LCM & GCD Calculator
Least common multiple and greatest divisor.
Standard Deviation Calculator
Sample and population deviation.
Combinations & Permutations
nCr and nPr for your numbers.
Random Number Generator
Random integers with stats and sorting.
Quadratic Equation Solver
Solve ax² + bx + c with roots & vertex.
Geometric Sequence
nth term and sum of a geometric series.
Rule of 72
Years to double money at any rate.
Pythagorean Theorem Calculator
Find the hypotenuse or a missing leg of a right triangle.
Triangle Area Calculator
Area from three sides using Heron's formula.
Circle Calculator
Circumference, area and diameter from a radius.
Sphere Calculator
Volume, surface area and diameter from a radius.
Cylinder Calculator
Volume, lateral area and total surface area.
About Math Calculators
Free math calculators for percentages, fractions, statistics, probability and everyday math.
Every tool runs entirely in your browser — instant results, no sign-up, no data sent to any server. All formulas are standard and published so you can verify the math yourself.
Frequently Asked Questions
Are these tools really free?
Yes. Every math tool on OmniCalcs is 100% free with no registration, and always will be.
Do I need to install anything?
No. All calculators run in your browser with pure HTML, CSS and JavaScript — nothing to download.
How accurate are the results?
Each tool uses standard, published formulas shown on its page, so you can verify every result yourself.