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.net Powerful JavaScript charts
About
RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 18 years old) and has a wealth of features making it an ideal choice to use for showing charts on your website.

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Version 7.20
Version 7.20 (released in June 2026) is the latest version of RGraph and the major change in this version is an update to the default values of properties making for better looking charts without having to set any properties. Read more about this and other changes in the changelog.

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Download
Get the latest version of RGraph (version 7.20, 9th June 2026) from the download page. You can read the changelog here. There's also older versions available, minified files and links to cdnjs.com hosted libraries.

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Latest forum posts
These are the latest support forum posts that have been posted or updated.

9th June, Richard
New version of RGraph: version 7.20
3rd June, Patrick
Question about installing RGraph
1st June, Ouja
How do I add a click event to a bar in my Bar chart?
8th May, Anthony Kuma
Does the SVG Line chart have outofbounds functionality?


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License
RGraph can be used for free under the GPL or if that doesn't suit your situation there's an inexpensive (£129) commercial license available.

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Updated multi-color Line chart demo

Written by Richard Heyes, RGraph author, on 17th August 2022

[No canvas support]

Here's an updated version of a demo that's already in the download archive. The colors have been changed, tickmarks added, it now uses the es6 spread operator when copying the configuration to the second chart, a key has been added and the way that the gradients are setup (using the beforedraw RGraph event). All the code for it is shown below and it should work as-is with version 6.08.

<script>

    // The data for both of the Line chart objects
    data = [8,4,6,2,1,5,3,3,4,8,9,8,4,1,3,4,7,8,8,5,6,4,1,2,3,4,2,3,1,5,3,5,1,5,6,8,7,9];
    
    // Draw a Line chart that shows the fill of the chart
    line = new RGraph.Line({
        id: 'cvs',
        data: data,
        options: {
            backgroundGrid: false,
            xaxisLabels: [
                '','Q1\n2014','',       '','Q2\n2014','',
                '','Q3\n2014','',       '','Q4\n2014','',
                '','Q1\n2015','',       '','Q2\n2015','',
                '','Q3\n2015','',       '','Q4\n2015',''
            ],
            filled: true,
            spline: true,
            yaxisScaleUnitsPost: '%',
            marginLeft: 50,
            marginTop: 50,
            marginBottom: 50,
            textColor: 'gray',
            colors: ['transparent'],
            keyLabelsSize: 16,
            linewidth: 1,
            textSize: 16,
            textFont: "'Calibri Light', sans-serif",
            events: {
                beforedraw: function (obj)
                {
                    var height = obj.canvas.height;

                    // Create the gradient that is used as the fill color
                    grad = obj.context.createLinearGradient(0,50,0,height - 50);

                    grad.addColorStop(0, '#0003');
                    grad.addColorStop(0.2, '#0003');
                    grad.addColorStop(0.2, '#f0f3');
                    grad.addColorStop(0.4, '#f0f3');
                    grad.addColorStop(0.4, '#0a03');
                    grad.addColorStop(0.6, '#0a03');
                    grad.addColorStop(0.6, '#00f3');
                    grad.addColorStop(0.8, '#00f3');
                    grad.addColorStop(0.8, '#f003');
                    grad.addColorStop(1.0, '#f003');
    
                    // Apply the gradient to the charts fill
                    obj.set({
                        filledColors: [grad]
                    });
                }
            }
        }
    }).draw();
    
    
    












    // Now create and draw the second, non-filled line that sits on
    // top of the fill.
    line2 = new RGraph.Line({
        id: 'cvs',
        data: data,
        options: {
            ...line.properties,
            filled: false,
            labels: null,
            yaxisLabels: false,
            backgroundGrid: false,
            tickmarksStyle: 'filledcircle',
            key: null,
            key: ['V Low','Low','Normal','High','V high'],
            keyColors: ['red','blue','#0a06','#f0f','black'],
            keyPosition: 'margin',
            keyPositionX: 65,
            keyColorShape: 'circle',
            responsive: [
                {maxWidth: null, width: 700, height: 300,options: {linewidth:2}},
                {maxWidth: 900, width: 500, height: 200,options: {linewidth:1}}
            ],
            events: {
                beforedraw: function (obj)
                {
                    var height = obj.canvas.height;

                    // Create the gradient that is used as the stroke color
                    grad = obj.context.createLinearGradient(0,50,0,height - 50);
                    grad.addColorStop(0, '#000');
                    grad.addColorStop(0.2, '#000');
                    grad.addColorStop(0.2, '#f0f');
                    grad.addColorStop(0.4, '#f0f');
                    grad.addColorStop(0.4, '#0a0');
                    grad.addColorStop(0.6, '#0a0');
                    grad.addColorStop(0.6, '#00f');
                    grad.addColorStop(0.8, '#00f');
                    grad.addColorStop(0.8, '#f00');
                    grad.addColorStop(1.0, '#f00');
        
                    obj.set({
                        colors: [grad]
                    });
                }
            }
        }
    }).draw();
</script>