Function plotter
Type a formula and see its graph at once. Draw several functions in different colours, move and zoom the coordinate grid, and slide the parameter a to watch a whole family of curves change. Asymptotes and jumps are drawn without false vertical lines. Type a formula such as x^2, sin(x) or a*x + 1, or tap an example. Drag the graph to move it, and use the wheel, a pinch or the + and − buttons to zoom. Hover or tap to read x and y.
How it works
- Type a formula in the box, for example x^2 - 3, sin(x) or 2*x + 1, or tap one of the examples.
- Press Add function to draw more graphs. Each one has its own colour, and the eye button shows or hides it.
- Drag to move the grid, zoom with the wheel, a pinch or the + and − buttons, and hover or tap to read the values. Use a in a formula and move the slider to change it.
Writing formulas
Use x as the variable and a as the parameter. You can write + − * / and ^ for powers, brackets, |x| for the absolute value, pi and e, and functions such as sin, cos, tan, sqrt, ln, log, exp and abs. A number before x or a bracket multiplies, so 2x and 3(x + 1) work too. Angles are in radians.
Asymptotes and gaps
Where a function is not defined, such as ln x for x ≤ 0 or 1/x at 0, the graph simply stops. Where the value jumps, as with tan x, the plotter checks the points in between and lifts the pen, so you never see a false vertical line across an asymptote.
Frequently asked questions
Can I use degrees?
The plotter works in radians, like most graphing tools. To use degrees, convert inside the formula: sin(x*pi/180) draws the sine with x in degrees.
Can I save the graph?
Yes. Save stores the current view as a PNG image, with the legend but without the trace cursor. Edit opens it in the photo editor, for example to add notes.
Is anything sent to a server?
No. The formulas are read and drawn in your browser, and your functions are only remembered on your own device.
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Ready to try it?
Open PictorX in your browser — no install, no credit card required to start.
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