How do I graph a function?

Simply type your equation in the input box using standard mathematical notation. For example, type 'x^2' for a parabola or 'sin(x)' for a sine wave. The graph will update automatically as you type.

Can I use variables like 'a' and 'b'?

Yes! You can define custom variables (sliders) in the Parameters section. If you have a slider named 'a', you can type an equation like 'a*x^2' and move the slider to see the graph change in real-time. These parameters are global and can be reused in all your equations.

How do I see the tangent line or area under a curve?

Go to the 'Calculus' tab. There you can enable the Tangent Line to see the slope at any point, or the Integration tool to visualize the area under the curve (or between two curves) using draggable points.

Can I download my graph as an image?

Yes, click the Download icon in the top-right corner of the graph. It will generate a high-resolution PNG image of your current view, including all axes, grid lines, and plotted functions.

Is this graphing calculator free?

Yes, CalcTools provides this 2D graphing calculator for free. There is no login required and it works on all modern browsers and mobile devices.

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Mathematics

Function Grapher

Interactive 2D graphing calculator. Visualize mathematical functions like linear, quadratic, and trigonometric equations. Perfect for students and teachers to explore algebra and calculus.

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How it Works

This tool uses a powerful mathematical parser to evaluate equations across a grid of thousands of points. It leverages SVG (Scalable Vector Graphics) for crisp rendering and standard browser technologies for interactive sliders and calculus analysis.