RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 15 years old) and has a wealth of features making it an ideal choice to show charts on your website.

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Get the latest version of RGraph (version 6.17) from the download page. There's also older versions available, minified files and links to cdnjs.com hosted libraries.

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RGraph can be used for free under the GPL or if that doesn't suit your situation there's an inexpensive (£99) commercial license available.

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I try download of graph with code below:
$(".test").append(`<a download href='${obj.canvas.toDataURL("image/png")}'>Test</a><br>`);
but when I download the graphic it has the wrong pointer value.

Is the chart showing the correct value when the button is pressed? Is there an animation involved?

Can you link to the page that the chart is on or put an example online? What happens if you put a regular, static link on the page for example:

<a href="#" onclick="location.href = myObject.canvas.toDataURL('image/png')">Test</a>

PS If the canvas is supposed to be white, try clearing it to white before drawing:

m = new RGraph.Meter({
    id: 'cvs',
    min: 0,
    max: 200,
    value: 98,
    options: {
    }
}).on('beforedraw', function (obj)
{
    RGraph.clear(obj.canvas, 'white');
}).draw();