Free online graphing calculator

A graphing calculator that shows you the answer, not just the picture

Type an equation and it is drawn immediately. Drag a slider and the curve moves with it. Ask for the roots and you get the coordinates to six figures, ready to copy into your homework, rather than a shape you have to squint at.

Everything runs inside your browser. There is no account, no download and no upload, so whatever you type stays on your own device. It works the same on a phone in a classroom as on a laptop at a desk.

What you can graph

The calculator works out what you mean from the shape of what you type, so there is no mode to switch between.

You type	You get
y = x^2 - 3x + 1	A parabola. The y = is optional.
x = y^2	A sideways parabola, sampled along the y-axis.
x^2 + y^2 = 25	A circle, traced as an implicit curve.
y < 2x + 1	A shaded half-plane with a dashed boundary.
y ≤ 2x + 1	The same region with a solid boundary, because the edge is included.
a*sin(b*x)	A sine wave with sliders for a and b.
{x > 0: ln(x), -ln(-x)}	A piecewise function with a different rule on each side.
sqrt(x){x < 4}	A curve restricted to part of its domain.
(3, 4)	A single plotted point, useful for marking a vertex or a solution.

How to use it

1. Type an expression in the first box. It is graphed as you type; there is no button to press.
2. Add more expressions with the plus button. Each one gets its own colour, and the dot beside it hides or shows that curve.
3. Move around by dragging the graph. Scroll or pinch to zoom. Hold Shift while scrolling to stretch the x-axis only, which is how you fit a tall, narrow curve into view.
4. Hover over a curve to read the exact coordinates at that point.
5. Open the Analyse tab and press the button to list every root, turning point and intersection in the visible window.
6. Export or share from the buttons above the graph.

Features worth knowing about

Sliders that animate a parameter

Type any letter other than x and y and the calculator offers to create a slider for it. Typing a(x - h)^2 + k gives you three, and dragging them is the fastest way to see what vertex form actually does to a parabola. Slider moves never pause the graph: the expression is compiled once, so only the redrawing happens as you drag.

Points of interest with real precision

Roots, local maxima and minima, y-intercepts, and the intersections between any two curves are found numerically to the limits of double precision, then listed with a copy button. The calculator distinguishes a root from a vertical asymptote, so 1/x correctly reports no root at zero, where a naive sign-change search would wrongly claim one.

Regression on your own data

The Data tab takes a table of points, either typed in or pasted straight from a spreadsheet, and fits eight model families: linear, quadratic, cubic, quartic, exponential, logarithmic, power and sinusoidal. You get the fitted equation, R squared, and for linear fits the correlation coefficient r. One button plots the fit on top of your points. If the data cannot support a model, such as an exponential fit on negative values, it says so rather than drawing a misleading curve.

Exports you can actually use

PNG gives you a high-resolution image at three times screen density. SVG gives you a real vector file with labelled axes and selectable text, which is the one to use for a printed worksheet, a lab report, or anything that will be resized. Most free graphing tools offer only a screenshot.

Links that carry the whole graph

Pressing Share encodes every expression, every slider and the exact window into the address. Because that information lives in the part of the URL after the #, it is never sent to our servers. We could not see your graph if we wanted to.

Syntax reference

Most things work the way you would write them on paper. These are the points where calculators differ from one another, so they are worth checking.

Write	Meaning	Note
2x, 3sin(x), (x+1)(x-2)	Multiplication	The multiplication sign is optional.
x^2, x^(1/3)	Powers	-x^2 means -(x^2), as in every textbook.
sqrt(x), cbrt(x), nthroot(3, x)	Roots	x^(1/3) correctly returns -2 at x = -8.
log(x)	Logarithm base 10	Matches US textbooks and the TI-84. Use log(2, x) for another base.
ln(x)	Natural logarithm
sin^-1(x) or arcsin(x)	Inverse sine	Not a reciprocal. For that, write 1/sin(x).
|x - 3|	Absolute value	abs(x - 3) works too.
5!, ncr(5, 2)	Factorial, combinations	Factorial extends to non-integers through the gamma function.
pi, e, tau	Constants	The symbols π and τ work if you paste them.
x_1, theta	Subscripts and Greek letters	Useful when a problem names its variables.

Learn how to use it properly

Each guide below is a worked walkthrough with a real graph you can open and change.

• How to graph a parabola

  Standard, vertex and factored form, and how to read each one off the curve.

• Finding x- and y-intercepts

  What the intercepts mean, and three ways to get them exactly.

• Domain and range from a graph

  Reading both off a curve, including the cases students lose marks on.

• Graphing piecewise functions

  Open and closed endpoints, and why the jump should not be joined up.

• Asymptotes explained

  Why 1/x and tan(x) break the line, and how to find every asymptote.

• Linear regression from data

  Line of best fit, r and R squared, and what they do and do not tell you.

See all guides →

The other calculators

The graphing calculator plots. These two answer the question that usually comes next.

• Derivative calculator

  Differentiate with the rule shown at each step, integrate, find turning points and inflections, and take limits.

• Statistics calculator

  Summary statistics, distributions, confidence intervals and hypothesis tests, with the working and exportable charts.

Frequently asked questions