Hong Life CalculatorsAll math & statistics tools
Arithmetic & numbers
- Ratio Calculator (simplify & scale A:B)
- Proportion Solver (a/b = c/x)
- Fraction Simplifier
- Decimal to Fraction Converter (incl. repeating)
- Fraction to Decimal (shows repeating part)
- Fraction Calculator (add, subtract, multiply, divide)
- Least Common Denominator (LCD) Calculator
- GCD & LCM Calculator
- Prime Factorization Calculator
- Prime Number Checker (next & previous prime)
- Divisors (Factors) of a Number Calculator
- Number Base Converter (binary, octal, decimal, hex, any base)
- Two’s Complement Calculator
- IEEE 754 Floating-Point Converter (32 & 64-bit)
- Exponent Calculator (xʸ)
- Nth Root Calculator
- Logarithm Calculator (any base, ln, log10)
- Antilog Calculator
- Scientific Notation Converter
- Significant Figures Calculator & Rounder
- Rounding Calculator (decimals, nearest 5/10/100, up/down)
- Percent Error Calculator
- Percent Difference Calculator
- Factorial Calculator (n!, double factorial)
- Permutation & Combination Calculator (nPr, nCr)
- Arithmetic & Geometric Sequence Calculator
- Fibonacci Number Calculator
- Modulo Calculator (a mod n, modular exponent)
- Chinese Remainder Theorem Calculator
- Average Calculator (mean, median, mode)
- Weighted Average Calculator
- Geometric & Harmonic Mean Calculator
- Roman Numeral Converter
- Number to Words Converter (English)
- Scale Calculator (drawing & map scale to real size and back)
- Golden Ratio Calculator (φ ≈ 1.618: longer part, shorter part, whole)
- Percent to Goal Calculator (progress %, remaining, pace needed)
- Least to Greatest Calculator (sort numbers & fractions in order)
- Absolute Change Calculator (final − initial, with relative change)
- Absolute Value Calculator (|x| of real numbers and |a + bi| of complex numbers)
- Associative Property Calculator (check (a + b) + c = a + (b + c) and (ab)c = a(bc))
- Consecutive Integers Calculator (find consecutive, even or odd integers from their sum)
- Digit Sum Calculator (sum of the digits of a number)
- Digital Root Calculator (repeated digit sum, additive persistence)
- Distributive Property Calculator (expand a(b + c) step by step)
- Divisibility Test Calculator (rules for 2 to 13, step by step)
- Egyptian Fractions Calculator (write a fraction as a sum of unit fractions)
- Expanded Form Calculator (place value, with multiplication & powers of 10)
- Fermat’s Little Theorem Calculator (check aᵖ⁻¹ ≡ 1 mod p, Fermat test)
- Floor and Ceiling Function Calculator (⌊x⌋, ⌈x⌉, truncation, fractional part)
- Greater Than or Less Than Calculator (compare numbers, decimals & fractions)
- Integer Calculator (add, subtract, multiply & divide with negative numbers)
- Long Addition Calculator (column addition with carrying, step by step)
- Long Subtraction Calculator (column subtraction with borrowing, step by step)
- Long Multiplication Calculator (partial products, step by step)
- Magic Square Calculator (make an n×n magic square, any order from 3)
- Order of Magnitude Calculator (nearest power of 10 & comparing two numbers)
- Partial Products Calculator (multiply by place value, step by step)
- Perfect Cube Calculator (is it a perfect cube? cube root & nearest cubes)
- Perfect Square Calculator (is it a perfect square? square root & nearest squares)
- Pi Experiments Calculator (estimate π with random points or Buffon’s needle)
- Place Value Calculator (find the place and value of a digit)
- Polish Notation Converter (infix ↔ prefix & postfix / reverse Polish)
- Powers of i Calculator (iⁿ for any whole-number exponent, with steps)
- Rational or Irrational Calculator (fractions, decimals, repeating decimals & roots)
- Rationalize the Denominator Calculator (square roots, cube roots & conjugates)
- Reciprocal Calculator (multiplicative inverse of a number, fraction or decimal)
- Root Mean Square Calculator (RMS / quadratic mean of a data set)
- Set Builder Notation Calculator (set-builder ↔ roster form)
- Sum of Products Calculator (Σxy, corrected sum of products & covariance)
- Triangular Numbers Calculator (n-th triangular number & triangular test)
- Fraction Exponent Calculator (x^(a/b) as a root, with both methods)
- Unit Rate Calculator (amount per one unit: per hour, per item, per kg)
- Babylonian Numbers Converter (base-60 cuneiform numerals ↔ decimal)
- Involute Function Calculator (inv α = tan α − α and its inverse, for gears)
- Mayan Numerals Converter (base-20 dots, bars and shell ↔ decimal)
- Average Percentage Calculator (simple vs weighted average of percentages)
- Time Percentage Calculator (what % of a day, week, month or year is it?)
Algebra
- Quadratic Equation Solver (ax² + bx + c = 0)
- Cubic Equation Solver (ax³ + bx² + cx + d = 0)
- Linear Equation Solver (ax + b = c)
- System of Equations Solver (2 variables)
- System of Linear Equations Solver (n × n, Gauss-Jordan)
- Polynomial Root Finder (any degree, numeric)
- Polynomial Evaluator (p(x) & derivative)
- Linear Inequality Solver (ax + b ? c)
- Complex Number Calculator
- Complex Number Rectangular ⇄ Polar & Powers (De Moivre)
- Binomial Expansion Calculator ((a x + b)ⁿ)
- Pascal’s Triangle Generator
- Exponential Equation Solver (a·bˣ = c)
- Newton-Raphson Root Finder (polynomial)
- Numerical Integration (Simpson’s rule) for Polynomials
- Polynomial Derivative & Integral Calculator
- Taylor Series Calculator (eˣ, sin, cos, ln(1+x))
- Summation Calculator (Σ of i^p, finite series)
- Gamma, Beta & Error Function Calculator
- Lambert W Function Calculator
- Completing the Square Calculator (step by step, vertex form & solutions)
- Factoring Trinomials Calculator (ax² + bx + c, ac method step by step)
- Multiplying Polynomials Calculator (expand & simplify the product)
- Polynomial Division Calculator (long division: quotient & remainder)
- Exponential Growth Calculator (growth & decay, doubling time, half-life)
- Doubling Time Calculator (exact vs rule of 70 and rule of 72)
- Truth Table Generator (AND, OR, NOT, XOR, implies, iff)
- Absolute Value Equation Calculator (solve |ax + b| = c or |ax + b| = cx + d)
- Adding and Subtracting Polynomials Calculator (combine like terms)
- Bessel Function Calculator (Jν(x) and Yν(x), first and second kind)
- Box Method Calculator (multiply polynomials with a grid / generic rectangle)
- Descartes’ Rule of Signs Calculator (possible positive & negative real zeros)
- Diamond Problem Calculator (two numbers from their product and sum)
- Direct Variation Calculator (y = kx: constant of variation & missing value)
- Inverse Variation Calculator (y = k/x: constant of variation & missing value)
- Error Function Calculator (erf, erfc and inverse erf)
- FOIL Calculator (multiply two binomials: first, outer, inner, last)
- Quadratic Inequality Calculator (solve & describe the graph of ax² + bx + c > 0)
- Interval Notation Calculator (interval ↔ inequality ↔ set-builder)
- Partial Fraction Decomposition Calculator (linear, repeated & quadratic factors)
- Perfect Square Trinomial Calculator (check & factor a² ± 2ab + b²)
- Power Set Calculator (list all subsets of a set)
- Quaternion Calculator (add, multiply, divide, norm, inverse & rotation)
- Rational Zeros Calculator (rational root theorem: candidates ±p/q & actual zeros)
- Subset Calculator (is A ⊆ B? number of subsets & proper subsets)
- Synthetic Division Calculator (table, quotient & remainder for x − k)
- Union and Intersection Calculator (A ∪ B, A ∩ B, difference & complement)
- Condense Logarithms Calculator (combine into a single logarithm)
- Expanding Logarithms Calculator (product, quotient & power rules)
- Dividing Radicals Calculator (simplify & rationalize the denominator)
- Exponential Form Calculator (logarithmic form ↔ exponential form)
- Exponential Function Calculator (find y = a·bˣ through two points)
- Multiplying Radicals Calculator (multiply & simplify square, cube and n-th roots)
- Collatz Conjecture Calculator (3n + 1 sequence: steps & highest value)
- Convolution Calculator (discrete convolution of two sequences)
- Harmonic Number Calculator (Hₙ = 1 + 1/2 + … + 1/n)
- Lagrange Error Bound Calculator (Taylor polynomial remainder estimate)
Geometry
- Triangle Calculator (3 sides → angles, area)
- Right Triangle & Pythagorean Theorem Calculator
- Law of Sines & Cosines Solver (SAS: two sides & included angle)
- Triangle Area Calculator (base × height, coordinates)
- Circle Calculator (area, circumference, diameter)
- Arc Length & Sector Area Calculator
- Ellipse Calculator (area, perimeter, eccentricity)
- Regular Polygon Calculator
- Rectangle & Square Calculator
- Trapezoid Calculator
- Parallelogram & Rhombus Calculator
- Polygon Area from Coordinates (Shoelace Formula)
- Pick’s Theorem Calculator
- Perimeter Calculator (triangle, rectangle, trapezoid, circle, sector & more)
- Crescent Area Calculator (circle with an overlapping circle cut away)
- Centroid Calculator (centre of a set of points, with optional weights)
- Conic Sections Calculator (identify Ax² + Bxy + Cy² + Dx + Ey + F = 0)
- Cycloid Calculator (arch length, area & point position of a rolling circle)
- Orthocenter Calculator (where the altitudes of a triangle meet)
- Quadrilateral Area Calculator (Bretschneider's formula or diagonals)
- Segment Addition Postulate Calculator (solve AB + BC = AC for x)
- Spiral Length Calculator (length of a roll, coil or Archimedean spiral)
- Star Shape Calculator (area & perimeter of a regular star polygon {p/q})
- Clock Angle Calculator (angle between the hour and minute hands)
- Complementary Angles Calculator (90° − θ in degrees and radians)
- Supplementary Angles Calculator (180° − θ in degrees and radians)
- Coterminal Angle Calculator (positive & negative coterminal angles, reference angle)
- Circle Theorems Calculator (inscribed, central, tangent & chord angles)
- Coin Rotation Paradox Calculator (how many turns a rolling coin makes)
- Square in a Circle Calculator (inscribed square: side, radius, areas)
- String Girdling Earth Calculator (add rope to a belt round the Earth: how high?)
- Tangent of a Circle Calculator (tangent length, tangent points & line equations)
- Pythagorean Triples Calculator (Euclid’s formula generator & triple checker)
- Similar Triangles Calculator (scale factor & missing sides, incl. right triangles)
- Triangle Inequality Theorem Calculator (can three sides make a triangle?)
- Area Calculator (rectangle, triangle, circle, trapezoid & more)
Solids
- Sphere Calculator (volume, surface area)
- Cylinder Calculator
- Cone & Frustum Calculator
- Pyramid Calculator (square or rectangular base)
- Cube & Rectangular Box Calculator
- Torus Calculator
- Spherical Cap & Hemisphere Calculator
- Prism Volume Calculator (any base)
- Ellipsoid & Capsule Volume Calculator
- Surface Area Calculator (cube, box, cylinder, cone, sphere, pyramid & more)
- Euler’s Formula for Polyhedra Calculator (V − E + F = 2: find vertices, edges or faces)
- Surface Area to Volume Ratio Calculator (SA:V of sphere, cube, box, cylinder)
- Tetrahedron Volume Calculator (regular edge or four vertex coordinates)
- Volume Calculator (cube, cylinder, cone, sphere, pyramid & more)
Coordinate geometry
- Distance & Midpoint Calculator (2D/3D)
- Equation of a Line from Two Points
- Distance from a Point to a Line
- Intersection of Two Lines Calculator
- Equation of a Circle Calculator (center-radius & general form)
- Circle Through Three Points Calculator
- Parabola Calculator (vertex, focus, directrix)
- Hyperbola Calculator (foci, eccentricity, asymptotes)
- Polar ⇄ Cartesian Coordinates Converter
- Spherical & Cylindrical Coordinates Converter
- Equation of a Plane Through Three Points
- Vertex Form Calculator (standard form ↔ vertex form of a parabola)
- Average Rate of Change Calculator (function over an interval)
- Linear Interpolation Calculator (find y between two points)
- Bilinear Interpolation Calculator (value inside a grid of four points)
- Catenary Curve Calculator (cable length & shape from span and sag)
- Coordinate Grid Calculator (which quadrant, distance from origin, reflections)
- Endpoint Calculator (find the other endpoint from one endpoint and the midpoint)
- Latus Rectum Calculator (parabola, ellipse & hyperbola)
- Line of Intersection of Two Planes Calculator (direction vector & point)
- Manhattan Distance Calculator (taxicab distance in 2-D and 3-D)
- Directed Line Segment Ratio Calculator (point dividing AB in m:n, internal & external)
- Rotation Calculator (rotate a point by an angle about the origin or any centre)
- Triangulation Calculator (distance to a point from two observation angles)
- Slope Calculator (from two points: slope, angle, line equation)
Trigonometry
- Trig Calculator (sin, cos, tan, sec, csc, cot)
- Inverse Trig Calculator (arcsin, arccos, arctan)
- Hyperbolic Functions Calculator (sinh, cosh, tanh & inverses)
- Degrees ⇄ Radians ⇄ Gradians Converter
- Slope % ⇄ Angle ⇄ Ratio Converter
- Double & Half Angle Calculator
- Unit Circle Calculator (reference angle, quadrant)
- Angle of Depression Calculator (from height & distance, or find distance / height)
- Phase Shift Calculator (amplitude, period, phase & vertical shift of sine and cosine)
Vectors & matrices
- Vector Calculator (dot, cross, angle, magnitude)
- Scalar Triple Product & Parallelepiped Volume
- Unit Vector & Direction Angles Calculator
- Matrix Determinant Calculator
- Matrix Inverse Calculator
- Matrix Multiplication & Addition Calculator
- RREF & Rank Calculator
- Matrix Power Calculator (Aⁿ)
- Eigenvalues & Eigenvectors Calculator (2×2, 3×3, n×n)
- Markov Chain Steady-State Calculator
- Adjoint (Adjugate) Matrix Calculator (adj A from cofactors, with A⁻¹)
- Characteristic Polynomial Calculator (det(λI − A) of a square matrix)
- Cholesky Decomposition Calculator (A = L·Lᵀ for symmetric positive-definite matrices)
- Cofactor Expansion Calculator (Laplace expansion of a determinant along any row or column)
- Cofactor Matrix Calculator (matrix of minors, cofactors and the adjugate)
- Column Space Calculator (basis and dimension of Col A from pivot columns)
- Matrix Condition Number Calculator (κ₂, κ₁ and κ∞ from singular values and norms)
- Corner Point Calculator (linear programming: vertices of the feasible region and optimum)
- Cramer’s Rule Calculator (solve Ax = b with determinants)
- Diagonalize Matrix Calculator (A = P·D·P⁻¹ with eigenvalues and eigenvectors)
- Gram–Schmidt Calculator (orthonormal basis from a set of vectors)
- Hadamard Product Calculator (entrywise A ∘ B of two matrices)
- LU Decomposition Calculator (P·A = L·U with partial pivoting)
- Linear Combination Calculator (find c₁, c₂, … with c₁v₁ + c₂v₂ + … = b)
- Linear Independence Calculator (are these vectors independent? dependence relation)
- Matrix Norm Calculator (1-norm, ∞-norm, Frobenius and spectral 2-norm)
- Null Space Calculator (basis of Nul A, nullity and the solutions of Ax = 0)
- Polar Decomposition Calculator (A = U·P: orthogonal times positive semidefinite)
- Pseudoinverse Calculator (Moore–Penrose A⁺ and least-squares solution)
- QR Decomposition Calculator (A = Q·R by Gram–Schmidt)
- SVD Calculator (singular value decomposition A = U·Σ·Vᵀ)
- Singular Values Calculator (σ of any matrix, rank, 2-norm and condition number)
- Tensor Product Calculator (Kronecker product A ⊗ B of two matrices)
Probability
- Probability Calculator (A and B, A or B, not A)
- Bayes’ Theorem Calculator (test accuracy)
- Odds ⇄ Probability Converter (fractional, decimal, American)
- Expected Value & Variance Calculator (discrete)
- Binomial Distribution Calculator
- Poisson Distribution Calculator
- Geometric Distribution Calculator (trials until first success)
- Hypergeometric Distribution Calculator (lottery, card draws)
- Normal Distribution Calculator (probability between values)
- Inverse Normal Calculator (percentile → value)
- Z-Score Calculator & Percentile
- Student’s t Distribution Calculator (p-value & critical t)
- Chi-Square Distribution Calculator (p-value & critical value)
- F Distribution Calculator (p-value & critical F)
- Exponential Distribution Calculator
- Uniform Distribution Calculator
- Dice Probability Calculator (sum of n dice)
- Birthday Paradox Calculator
- Lottery Odds Calculator (pick k of n, + bonus ball)
- At Least Once Probability Calculator (repeated tries)
- Coin Flipper (flip a fair coin online: heads or tails)
- Dice Roller (roll d6, d20 or any dice online, with modifier & drop lowest)
- Monty Hall Problem Simulator (switch or stay? 3 or more doors)
- Expected Utility Calculator (risky choices: certainty equivalent & risk premium)
- Prisoner’s Dilemma Calculator (payoff matrix & repeated-game strategies)
- Dating Theory Calculator (37% rule: secretary problem / optimal stopping)
- Bertrand’s Box Paradox Calculator (gold & silver coins: why 2/3, not 1/2)
- Bertrand’s Paradox Calculator (random chord: 1/3, 1/2 or 1/4?)
- Boy or Girl Paradox Calculator (two-child problem: 1/3, 1/2 or 13/27?)
- Chebyshev’s Theorem Calculator (minimum share within k standard deviations)
- Parrondo’s Paradox Calculator (two losing games that win when mixed)
- Relative Risk Calculator (RR, odds ratio, risk difference & NNT with confidence intervals)
- Roulette Payout Calculator (payout odds, house edge & expected loss per bet)
- Two Envelopes Paradox Calculator (should you switch? expected value explained)
- Venn Diagram Calculator (2 or 3 sets: union, regions, “only” counts)
- Beta Distribution Calculator (PDF, CDF, mean, mode, variance)
- Central Limit Theorem Calculator (standard error & probability for a sample mean)
- Continuity Correction Calculator (binomial to normal: =, ≤, ≥, between)
- Lognormal Distribution Calculator (PDF, CDF, mean, median, mode)
- Negative Binomial Distribution Calculator (probability of the r-th success)
- Rayleigh Distribution Calculator (PDF, CDF, mean, median, mode)
- Random Number Generator (range, count, no repeats)
Statistics
- Standard Deviation Calculator (sample & population)
- Descriptive Statistics Calculator (summary)
- Quartile, IQR & Box Plot Calculator (outliers)
- Percentile & Percentile Rank Calculator
- Trimmed Mean Calculator
- Correlation Coefficient Calculator (Pearson & Spearman)
- Linear Regression Calculator (least squares)
- Quadratic & Exponential Regression Calculator
- Confidence Interval Calculator (mean)
- Confidence Interval for a Proportion (Wald & Wilson)
- Sample Size Calculator (survey, margin of error)
- Margin of Error Calculator (polls)
- One-Sample t-Test Calculator
- Two-Sample t-Test Calculator (Welch & pooled)
- Paired t-Test Calculator
- Two-Proportion z-Test Calculator
- Chi-Square Test of Independence Calculator
- Chi-Square Goodness-of-Fit Calculator
- One-Way ANOVA Calculator
- Mann-Whitney U Test Calculator
- Statistical Power & Sample Size (two-group t-test, Cohen’s d)
- Effect Size Calculator (Cohen’s d, Hedges’ g)
- Frequency Table & Histogram Bins Calculator
- Mean Absolute Deviation (MAD) Calculator
- Standard Error of the Mean Calculator
- Normal Approximation to the Binomial
- Moving Average Calculator (SMA & EMA)
- IQ Percentile Calculator (score → percentile, rarity, z-score)
- Covariance Calculator (sample & population, with correlation)
- Empirical Rule Calculator (68–95–99.7 rule ranges)
- Pie Chart Calculator (percentages & slice angles from your data)
- Critical Value Calculator (z, t, chi-square & F; one- or two-tailed)
- P-Value Calculator (from a z, t, chi-square or F statistic)
- Hypothesis Testing Calculator (z test, t test, one-proportion test)
- Constant of Proportionality Calculator (k = y/x from a table; direct or inverse)
- Index of Qualitative Variation Calculator (IQV for categorical data)
- Pooled Standard Deviation Calculator (two or more groups from n and SD)
- Skewness Calculator (G₁, g₁, Pearson & Galton skewness, kurtosis)
- Standard Deviation Index Calculator (SDI for proficiency testing & peer comparison)
- Sum of Squares Calculator (SS = Σ(x − x̄)², Σx² and variance)
- Benford's Law Calculator (first-digit test of your data)
- Class Width Calculator (histogram classes, boundaries & midpoints)
- Dot Plot Calculator (text dot plot, mode, median & spread)
- Exponential Growth Prediction Calculator (fit a growth rate to your data, then forecast)
- Frequency Polygon Calculator (class midpoints & points to plot)
- Stem and Leaf Plot Calculator (stemplot with key, median & range)
- Bonferroni Correction Calculator (adjusted α & p-values for multiple tests)
- Cubic Regression Calculator (least-squares y = ax³ + bx² + cx + d)
- Degrees of Freedom Calculator (t-tests, Welch, chi-square, ANOVA, regression)
- Exponential Regression Calculator (fit y = a·bˣ to data)
- Fisher's Exact Test Calculator (2×2 table, one- and two-sided p)
- McNemar's Test Calculator (paired 2×2 table: χ² and exact p)
- Point Estimate Calculator (MLE, Wilson, Laplace & Jeffreys for a proportion)
- Polynomial Regression Calculator (least-squares fit, degree 2 to 6)
- Residual Calculator (residuals e = y − ŷ, sum of squares, largest residual)
- Youden Index Calculator (J = sensitivity + specificity − 1)
FAQ
How accurate are the results?
Calculations run in your browser with double-precision numbers (about 15 significant digits); special functions are accurate to at least 7 digits.
Checked 8 Nov 2026.