Use a truly full scientific calculator online, free: definite integration, differentiation, summation, matrices, vectors, complex numbers, statistics with regression, quadratic / cubic / simultaneous equation solving, and base-N binary, octal and hexadecimal arithmetic — 403 functions across 10 modes in a Casio fx-991ES PLUS–style layout. It runs in your browser with a natural textbook display: no download, no sign-up, and it works offline as a PWA. The interactive calculator is directly below; scroll past it for the feature guide and FAQ, or visit the calculator guides and the complete documentation.
A truly scientific calculator online — Casio fx-991ES PLUS–style modes in your browser. Not a basic calculator with a few extra buttons: 403 functions across 10 modes, completely free from Appynox.
Most online "scientific" calculators only cover trigonometry, logarithms and roots. This one does the full job — calculus, matrices, complex numbers, statistics, equation solving and base-N — with a natural textbook display, no download and no sign-up. It even works offline once loaded.
Search "scientific calculator" and most results — including big names like Desmos and Google — are really basic calculators with trig and log keys bolted on. A genuine scientific calculator goes much further. Here's the difference:
| Capability | Basic "scientific" calculators | This calculator |
|---|---|---|
| Trigonometry, logarithms, powers & roots | Yes | Yes |
| Fractions & natural textbook display | Rarely | Yes |
| Definite integration & differentiation | No | Yes |
| Summation (Σ) of series | No | Yes |
| Matrices & vectors | No | Yes |
| Complex numbers (a+bi, polar) | No | Yes |
| Equation solver (quadratic, cubic, simultaneous) | No | Yes |
| Statistics & 7 regression types | No | Yes |
| Base-N (binary / octal / hex) & bitwise | No | Yes |
| Distributions, constants & unit conversions | No | Yes |
Compute definite integrals numerically. Enter ∫(f(x), a, b) — supports polynomial, trigonometric, exponential, and logarithmic integrands.
Numerical differentiation at any point. Use d/dx(f(x), a) to find the derivative of any expression instantly.
Evaluate finite sums with Σ(f(x), start, end). Useful for series, sequences, and discrete mathematics.
Add, subtract, multiply matrices up to 3×3. Compute determinant, inverse, and transpose with a few button presses.
Arithmetic in rectangular a+bi and polar r∠θ form. Includes modulus, argument, and conjugate.
Solve quadratic, cubic, and simultaneous linear equations (2–3 unknowns). Get all real and complex roots instantly.
Convert between binary, octal, decimal, and hexadecimal. Bitwise AND, OR, XOR, XNOR, NOT supported.
Mean, standard deviation, variance, and 7 regression types: linear, quadratic, logarithmic, exponential, power, and inverse.
Enter and simplify fractions and mixed numbers. Toggle between exact fraction and decimal display with S⇔D.
No account and no manual required — but if you want the full walkthrough, here's how the six steps work.
MODE and choose COMP for everyday calculations, or CMPLX, STAT, BASE-N, EQN, MATRIX, VECTOR, or TABLE for specialized math.∫dx or x!); ALPHA gives you the red variable/letter functions. Available keys light up while a modifier is held.= to evaluate. Trailing brackets close automatically, so cos(45 evaluates the same as cos(45).STO/RCL save values to variables A–F, X, Y; the history panel keeps every past calculation one tap away.∫( then your function, a comma, the lower limit, a comma, and the upper limit. Example: ∫(x², 0, 3) returns 9. Supports any expression math.js can evaluate.d/dx(f(x), a) to compute the numerical derivative at point a. Example: d/dx(x³, 2) returns 12. Works for trigonometric, exponential, logarithmic, and polynomial functions.= to get both roots — real or complex.3+4i (rectangular) or 5∠53.13 (polar). The calculator returns the result in whichever form you choose and supports modulus, argument, and conjugate operations.det), inverse, and transpose operations.Enter computes the result, Backspace deletes, Escape clears, arrow keys move the cursor, and ↑ ↓ scroll through expression history. ^ for powers, % for percent, ! for factorial.