About Formula Hub
What this site is
Formula Hub is a free mathematics reference built for students, professionals, and anyone who needs to understand a math concept quickly and clearly. The site covers algebra, statistics, geometry, pre-calculus, calculus, and arithmetic through two sections: plain-English lessons that explain concepts from first principles, and calculators that do the computation and show the formula.
Everything on the site is free. There is no signup, no paywall, and no premium tier. The site is supported by advertising.
Editorial standards
Every lesson page on Formula Hub is written to meet the following standards:
Mathematical accuracy: All formulas, worked examples, and numerical results are verified against established references. Where possible, worked examples include a check step so the answer can be independently verified.
Source grounding: Explanations are grounded in standard mathematical curricula and reference materials. Each lesson page includes a Sources and Further Reading section linking to primary sources including Wikipedia, Khan Academy, MIT OpenCourseWare, NIST, and peer-reviewed publications where relevant.
Plain English: The goal is for every explanation to be understandable to someone encountering the topic for the first time, without sacrificing mathematical correctness. Concepts are explained from first principles before formal notation is introduced.
No advertising influence: Lesson content is written independently of advertising relationships. Calculators link to relevant lessons and vice versa because they are genuinely related, not for commercial reasons.
Sources and references
Formula Hub draws on the following categories of sources:
Primary mathematical references: Wikipedia's mathematics articles, which are subject to community review and cite academic sources. The NIST Digital Library of Mathematical Functions and the NIST Engineering Statistics Handbook, both published by the US National Institute of Standards and Technology.
Educational references: Khan Academy, MIT OpenCourseWare, and Paul's Online Math Notes (Lamar University), which are widely used in mathematics education.
Academic publications: Where specific claims relate to statistical practice or mathematical history, we cite peer-reviewed sources including journals published by the American Statistical Association and Nature.
Specific source links appear at the bottom of each lesson page under Sources and Further Reading.
Corrections
If you find a mathematical error or an explanation that is unclear, the site can be contacted through the domain. We take accuracy seriously and will correct errors promptly.
Coverage
The site currently covers:
Arithmetic: Fractions, decimals, percentages, factors and multiples, negative numbers.
Algebra: Linear equations, order of operations, functions, quadratic equations, factoring, exponent rules, systems of equations, inequalities, slope-intercept form, ratios and proportions, absolute value, polynomials.
Statistics: Standard deviation, normal distribution, p-values, confidence intervals, hypothesis testing, correlation vs causation, mean vs median, probability, permutations and combinations.
Geometry: Pythagorean theorem, area and perimeter, circle formulas, volume formulas, types of angles and triangles, coordinate geometry.
Pre-Calculus: Logarithms, exponential growth and decay, trigonometry, sequences and series, functions and transformations, vectors.
Calculus: Limits, derivatives, differentiation rules, chain rule applications, integration, the fundamental theorem of calculus.
New lessons are added regularly. Calculator coverage spans finance, business, statistics, geometry, health, percentages, conversions, and algebra.