FREE ONLINE MATH TOOL

Scientific calculator
with fractions & graphs.

Calculate fractions, roots, logarithms and trigonometry with textbook-style input. Solve an equation or enter a function in the same screen, then show its graph when you need it.

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Scientific calculator

NATURAL DISPLAY

WEB CALCULATORSCIENTIFIC · GRAPHING

Natural DisplayONE WORKSPACE

Digits M = 0

AUTOMATH I/O

WRITE YOUR MATH Calculate · solve · graph

Write an expression, function or equation.

Enter calculate · ←→ move inside expressions · Esc clear

TRY IT

More tools: Fraction calculator with steps and mixed numbers

01 / NATURAL INPUT

Looks like your textbook.

Real fractions, stacked powers and roots. Read your expression exactly as you intended.

02 / VISUAL THINKING

See the bigger picture.

Plot functions together, inspect their values and explore how an equation behaves.

03 / ROOM TO EXPLORE

How to use the
scientific calculator

Start with a question. Write it in one screen.
Keep the useful working.

Write an expression naturally

Write a number expression, a function such as y = x², or an equation such as 2x + 3 = 7 in the same LCD. Press = or Enter: the calculator detects the input and displays its answer or solutions in place. When a graph is available, select Show graph to open it; Hide graph restores the compact display. The small “= equation” key inserts an equality; the large = key runs it. Type from your keyboard or choose a key. For ½ + ⅓, insert a fraction, fill the numerator, press the down arrow for the denominator, then the right arrow to leave the fraction. Press Enter or = to calculate.

Choose the right angle unit

DEG treats 30 as 30 degrees, so sin(30) = ½. In RAD, sin(π/6) = ½. GRAD uses 400 gradians per full turn. Functions, equations with trigonometry and graphing use radians, independently of the angle setting for ordinary number calculations.

Keep exact answers when it matters

⅓ + ⅙ gives ½, with 0.5 shown beneath. √50 simplifies to 5√2. Use Exact ⇄ decimal to change the main display. Ans recalls your last answer; M+, M− and MR manage a separate memory value.

Worked scientific calculator examples

Enter these expressions in the calculator above. Each example explains how to check the result.

Add fractions: ⅓ + ⅙

Use a common denominator of 6: ⅓ becomes ²⁄₆, so ²⁄₆ + ⅙ = ³⁄₆ = ½. The calculator shows the exact fraction and its decimal value, 0.5. Use the fraction key or type / to create a stacked fraction.

Simplify a square root: √50

Factor 50 into 25 × 2. Since √25 = 5, √50 = 5√2, approximately 7.07106781186548. Exact form preserves the radical; the decimal is rounded to the selected display precision.

Calculate sine: sin(30)

Select DEG for this numerical expression: sin(30°) = ½. In RAD, enter sin(π/6) for the same result because 30° × π/180 = π/6 radians. The angle setting changes the meaning of a number inside a trigonometric function.

Solve an equation: 2x + 3 = 7

Subtract 3 from both sides to obtain 2x = 4, then divide by 2 to get x = 2. Insert the equality using the small equation key and press the large = key to solve. Substituting 2 gives 2 × 2 + 3 = 7.

Graph a function: y = x² − 4

Enter the function, calculate, then select Show graph. At x = 0, y = −4; at x = −2 and x = 2, y = 0. These points locate the vertex and the two x-axis crossings. Hide graph returns to the compact calculator display.

Multiply complex numbers: (2 + 3i)(1 − i)

Expand to 2 − 2i + 3i − 3i². Using i² = −1 gives 5 + i. This is a complex result, so it is not a point on the real-valued function graph.

Return to the scientific calculator · Equation-solving method and limits

How equations and graphs are calculated

Exact solutions and numerical searches

The calculator attempts symbolic solutions for supported polynomial equations up to degree four, checking candidate values against the equation. When symbolic solving does not return a result, supported real-valued equations use a numerical search from −10 to 10 with a sampling step of 0.02 and bisection of sign-changing intervals. This can miss roots that touch the axis, closely spaced roots, or solutions outside that interval. “No root found” is not proof that an equation has no solution.

What an equation graph means

For an equation, the graph shows the left side minus the right side. Its real zeros are candidate solutions; check that both original sides are defined there. For y = f(x), the graph shows f(x) itself. Trigonometric functions in equations and graphs always use radians. Complex solutions are displayed as answers but are not plotted on the real graph.

Supported input and limits

Use arithmetic, parentheses, fractions, powers, roots, logarithms, trigonometric functions and complex numbers for numerical calculations. Equations must contain one equality and one single-letter unknown. Function graphs use x. Systems of equations, inequalities and implicit curves such as x² + y² = 1 are not supported in this workspace.

Checking a result

Substitute a proposed solution into the original equation, confirm the angle unit and inspect domain restrictions. Graphs use finite samples and floating-point arithmetic, so a plotted line may miss a discontinuity or narrow feature. Increase or decrease the graph scale and use the value table to inspect individual points.

A USEFUL REFERENCE

Scientific calculator functions and conventions

Order of operations

Parentheses group first, powers come before multiplication and division, then addition and subtraction. −2² = −4, while (−2)² = 4. Write parentheses explicitly when a fraction or implied multiplication could be ambiguous.

Logs, powers and percentages

ln is the natural logarithm, with base e. log uses base 10. Shift reveals inverse trigonometric and hyperbolic functions. Percent means division by 100: 200 × 15% = 30; 200 + 15% = 200.15.

Complex numbers

Use i for √−1. The principal square root of −4 is 2i. Multiplication follows ordinary algebra with i² = −1; for example, (2 + 3i)(1 − i) = 5 + i. Complex branches follow the computation library’s principal-value conventions.

Precision and limitations

The scientific engine works at 21 significant digits and offers 10, 15 or 20 display digits. Graphs and numerical tools use floating-point arithmetic. Screen rounding is not an uncertainty estimate. Graphs sample finite points and can miss narrow features; never infer continuity from a plotted line alone.

Scientific calculator questions

Can I enter fractions with my keyboard?

Yes. Type / or choose the fraction button to insert a textbook-style fraction. Fill the numerator and denominator, using the arrow keys to move between them. Empty fraction slots must be completed before calculating.

How do I show or hide a graph?

Enter a function such as y = x² − 4 or a supported equation and calculate. When graphing is available, select Show graph beneath the answer. Select Hide graph to close it. A numerical expression such as 2 + 3 does not need a graph.

Is this a Casio calculator?

No. This is an independent web calculator, inspired by familiar scientific-calculator workflows. It is not affiliated with Casio and does not claim complete model compatibility. The calculator uses one input screen with optional graphs. Hardware-specific menus, the full Casio function catalog and exam certification are not included.

Why does my expression show an error?

Check for empty fraction slots, unmatched parentheses, missing arguments or unknown variables. Division by zero has no finite answer. Graphs require a real-valued function of x; non-real values are omitted. An undefined answer is never replaced by zero.

Are my calculations stored or sent anywhere?

Inputs, answers, memory and history stay in this browser tab and are cleared on reload. There is no analytics, advertising or account system in this version. Math libraries and fonts are served with the website. Your web server may still log ordinary page and asset requests.

How are results computed?

Natural input uses MathLive. Exact and scientific evaluation uses the Cortex Compute Engine. Automatic numerical equation solving searches a bounded interval and may not find every root. Check inputs and assumptions before using a result in assessed or consequential work.

About this project

Web Calculator is an independent collection of browser-based mathematical tools. This new edition starts with the scientific calculator. We publish the available methods and limitations above, and expand only as tools are checked. To report a reproducible error, email infos@web-calculator.net with the expression, mode and expected result; do not include personal or sensitive data.

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Scientific calculator
with fractions & graphs.