What is X% of Y?

What is % of ?

Result

—

How to use the percentage calculator

Each tab above solves a different type of percentage problem. Type your numbers into the fields and the result updates instantly — no need to press a button.

X% of Y

Use this when you know a rate and a total, and need the actual amount.

Example: a 20% tip on a $45 restaurant bill → enter 20 and 45 to get $9.

X is what % of Y

Use this to see how one number compares to another as a percentage.

Example: you scored 42 out of 60 on a test → enter 42 and 60 to get 70%.

% Change

Use this to measure growth, discounts, or price changes between two values.

Example: rent went from $1,200 to $1,320 → enter 1200 and 1320 to see a 10% increase.

Fast everyday calculator

0

How to use the calculator

Tap the digits and operators just like a physical calculator. The running total shows above the display, and AC clears everything while ⌫ removes the last digit. The e and π buttons drop in Euler's number or Pi as a starting value for scientific-style calculations.

Splitting a bill

$86.40 shared between 4 people: enter 86.4 ÷ 4 to get $21.60 each.

Running a total

Adding up groceries: 12.5 + 4.2 + 7.99 gives you the subtotal instantly.

Quick multiplication

Estimating a project cost: 45 × 8 for 8 hours at $45/hour.

Enter a simple linear equation — get X instantly.

Result

Enter an equation above

How to use the equation solver

Type a linear equation with one unknown (any letter works, though x is the default) and one = sign. The value of X appears as you type — there's no separate "solve" button to click.

Basic equation

2x + 5 = 15 → x = 5. Useful for simple word problems like "double a number, add 5, get 15."

Variable on both sides

3x - 4 = 2x + 10 → x = 14. Handles the unknown appearing on either side of the equal sign.

Division

x/2 + 3 = 7 → x = 8. Fractions of the unknown are supported directly.

With a constant

x + e = 10 → x ≈ 7.28, using Euler's number automatically.

Type a function of x — the graph and analysis update instantly.

Y-intercept

—

X-intercept(s)

—

Increasing on

—

Decreasing on

—

Positive on

—

Negative on

—

Extrema (local max / min)

—

Results are calculated numerically within the displayed view range and are meant to help you check your work — always confirm important homework answers with your teacher or textbook.

How to use the function grapher

Type any function of x using + - * / ^, parentheses, and functions like sin, cos, sqrt, abs, log, and ln. The graph and every result below update as you type — move your mouse (or finger) over the graph to read off any point.

Quadratics

x^2 - 4 shows a parabola with two x-intercepts and a minimum at (0, -4).

Linear functions

-2x + 3 is a straight line — check the slope's sign against the increasing/decreasing result.

Cubic functions

x^3 - 3x has both a local maximum and a local minimum — a great way to check turning points.

Roots and fractions

sqrt(x) and 1/x show how the tool handles restricted domains and asymptotes.

Quick Math Tools