Chartjs-Chart.js plot live data

You are trying to create the chart again everytime which is inneficient and afaik not even possible, if I am correct chart.js throws an error that the canvas is already in use, to achieve what you want you need to create the chart once outside the function, store in in a variable and then in your graphPoints function you call myChart.data.datasets[0].data.push(...arr) after that you can call the update method on chart.js like so: mychart.update() this will make chart.js update and render all the new values.