How to Graph Functions Online
Seeing a function as a curve makes it far easier to understand than a formula alone. This graphing calculator plots up to two functions of x, lets you read values by hovering over the graph, and automatically finds roots, intersections, the minimum and maximum, and the y-intercept.
How to enter a function
Type your function using x as the variable. Some examples:
| You type | Meaning |
|---|---|
x^2 - 4 | Parabola x² − 4 |
2x + 1 | Straight line with slope 2 |
3sin(x) | Sine wave with amplitude 3 |
sqrt(x) | Square root of x |
1/x | Hyperbola |
exp(-x^2) | Bell-shaped curve |
abs(x - 2) | V-shaped graph |
You can write multiplication without a × sign, such as 2x or 3(x + 1). Trigonometric functions use radians here.
What the calculator finds for you
- Roots – the x-values where the graph crosses the x-axis (f(x) = 0).
- Intersections – points where f(x) and g(x) meet, useful for solving equations like x² − 4 = 3sin(x).
- Minimum and maximum – the lowest and highest values within your chosen range.
- Y-intercept – the value of the function at x = 0.
- Table of values – 21 evenly spaced points you can download as CSV.
Choosing a good range
Set "X from" and "X to" to cover the part of the graph you care about. The Y axis scales automatically, ignoring extreme spikes such as those near the asymptotes of tan(x) or 1/x. If you want a fixed view, switch the Y axis to "Fixed" and enter your own limits.
Tips for students
- To solve an equation like f(x) = g(x), graph both sides and read the intersections.
- Roots are found numerically, so they are shown to about 6 significant figures.
- Zoom in on a region by narrowing the X range to see detail.
Disclaimer: Results are provided for general use and education. Please double-check any calculation that matters for exams, work or legal purposes.