What Desmos Does and How to Start

Desmos is a free online graphing calculator that lets you plot equations, see how they look as graphs, and explore how changing numbers changes the shape. You don't need to install anything — you open it in a web browser at desmos.com, type an equation, and it draws the graph instantly. It works on phones, tablets, and computers.

The main screen has a blank grid on the right and an input area on the left where you type. When you type an equation like y = 2x + 3, Desmos draws the line immediately. You can zoom in and out by scrolling, drag the grid around to see different parts, and add as many equations as you want — each one shows up in a different color.

Desmos is useful if you're learning algebra or precalculus, checking your homework, or just curious what an equation looks like. It's also free, which matters if you don't want to buy a graphing calculator.

Key Takeaways

  • Go to desmos.com in any web browser and start typing equations directly into the input box on the left side.
  • Use standard notation: y = for functions, x^2 for squares, sqrt(x) for square roots, and sin(x) for trigonometric functions.
  • Click the colored circle next to each equation to change its color, or click the three dots to delete it or adjust its settings.
  • Scroll to zoom in and out, or click and drag the grid to move around and see different parts of your graph.
  • Use sliders to change numbers in your equation and watch the graph move in real time — click the plus sign next to a number to create a slider.

Typing Equations Desmos Understands

Desmos uses fairly standard math notation, but a few symbols work differently than you might expect. Multiplication uses an asterisk: 2*x instead of 2x. Division uses a forward slash: y = 10/x. Powers use a caret: x^2 for x squared, x^3 for x cubed.

For square roots, type sqrt(x). For absolute value, type abs(x). Trigonometric functions are sin(x), cos(x), and tan(x) — Desmos assumes you're working in radians unless you tell it otherwise. If you need degrees, write sin(x°) with the degree symbol, or multiply by π/180.

You can also use inequalities. Type y < 2x + 1 and Desmos shades the region below the line. Use >, <=, or >= to shade different areas. This is useful for visualizing systems of inequalities or understanding what "less than" means on a graph.

Adding, Editing, and Organizing Multiple Equations

Each equation you type goes into its own row in the input area. Click in a new row and type another equation — Desmos draws it in a different color automatically. You can have dozens of equations on the same graph, and each one stays visible until you delete it.

To change an equation, click on it in the input area and edit the text. The graph updates as you type. To delete an equation, click the three-dot menu next to it and select delete, or just select all the text and press backspace. To change the color of a line, click the colored circle next to the equation — a palette appears and you can pick a new color.

If you want to hide an equation without deleting it, click the eye icon next to it. The line disappears from the graph but the equation stays in your list. This is helpful if you're comparing two versions of the same equation and want to toggle between them.

Using Sliders to Change Numbers and See Patterns

One of Desmos's most useful features is sliders. If you type an equation like y = mx + 2 where m is a letter instead of a number, Desmos notices and offers to create a slider for m. Click the plus sign that appears next to the equation, and a slider bar shows up below the graph. Drag the slider left and right, and the line rotates in real time.

Sliders help you understand what each part of an equation does. Slide m in y = mx + 2 and watch the slope change. Slide the 2 (if you make it a variable like y = 2x + b) and watch the line move up and down. This is much faster than typing new numbers over and over.

You can customize a slider by clicking the three dots next to it. Set the minimum and maximum values, the step size (how much it moves each time you drag), and the starting value. For example, if you're exploring y = a*sin(x), you might set the slider for a to go from -5 to 5 in steps of 0.1.

Zooming, Panning, and Adjusting the View

The grid starts with a standard view — usually from about -10 to 10 on both axes. Scroll your mouse wheel up to zoom in (make things bigger) or down to zoom out (make things smaller). On a touchpad, use the pinch gesture. On a phone or tablet, pinch with two fingers.

To move around the graph without changing the zoom level, click and drag the grid. The axes move with your drag, so you can see different parts of the graph. This is useful if your equation goes off the visible area and you need to find where it is.

To reset the view to the default, click the wrench icon in the top right corner and select "Reset zoom". You can also set custom axis ranges here — type in the minimum and maximum values for x and y if you want a specific view. This is helpful if you're zoomed way in and want to see the whole picture again quickly.

Finding Points, Intersections, and Using Tables

Click anywhere on a line and Desmos shows you the coordinates of that point. This is useful for reading values off the graph without having to estimate. If you click near where two lines cross, Desmos highlights the intersection point and shows its coordinates — this is how you can solve systems of equations visually.

You can also view your equation as a table of values. Click the three dots next to an equation and select "Convert to table". A table appears showing x and y values. You can scroll through the table, or click on a value in the table to see that point highlighted on the graph. This is useful if you need exact numbers rather than just the visual shape.

To add your own points to the graph, type them as ordered pairs: (2, 5) or (0, -3). Each point shows up as a dot. You can add a list of points by typing (1, 2), (3, 4), (5, 6) all in one input row, and Desmos plots them all.

Saving Your Work and Sharing Graphs

If you create a Desmos account (free, using an email address), your graphs save automatically. Click the menu icon (three horizontal lines) in the top left and select "Sign in" to create an account. Once you're signed in, every graph you make is saved to your account and you can come back to it later.

To share a graph with someone else, click the share button (arrow icon) in the top right. Desmos gives you a link you can copy and send. Anyone who opens that link sees your graph exactly as you left it — they can zoom and pan, but they can't edit your original unless you give them permission to do so.

You can also download your graph as an image (PNG file) by clicking the menu icon and selecting "Download as PNG". This is useful if you need to put the graph in a document or email it to someone who doesn't use Desmos.

Frequently Asked Questions

Can I use Desmos on my phone?

Yes. Desmos works in any web browser on a phone or tablet — just go to desmos.com. There's also a free Desmos app for iPhone and Android if you prefer a dedicated app, but the website version works just as well.

How do I type special symbols like π or √?

You don't need to. Type pi for π and sqrt(x) for the square root symbol. Desmos understands these words and converts them automatically. For other functions, use the word form: abs(x) for absolute value, log(x) for logarithm.

What if my equation doesn't show up on the graph?

The equation might be outside the visible area. Try clicking the wrench icon and selecting "Reset zoom" to go back to the default view. If that doesn't work, check your equation for typos — make sure you're using * for multiplication and ^ for powers. Desmos shows an error message if it doesn't understand your input.

Can I graph 3D equations or polar coordinates?

Desmos's main calculator does 2D graphs only. However, Desmos has a separate 3D calculator at desmos.com/3d that lets you graph three-dimensional equations. For polar coordinates, use the standard conversion: type equations in terms of r and θ (theta), and Desmos will plot them in polar form.

Is there a way to solve equations automatically?

Not directly — Desmos is a graphing tool, not a solver. But you can solve equations visually by graphing both sides and finding where they intersect. For example, to solve 2x + 3 = 7, graph y = 2x + 3 and y = 7, then click where they cross to see the answer.