A circle arc
<!DOCTYPE html> <html> <head> <style> #canvas { /*from w w w. j av a 2s .c om*/ border:1px solid #03F; background:#CFC; } </style> </head> <body> <canvas id="canvas" width="640" height="480"></canvas> <script> let context = document.getElementById('canvas').getContext('2d'); context.beginPath(); context.strokeStyle = "black"; context.lineWidth=5; context.arc(100, 100, 20, (Math.PI/180)*0, (Math.PI/180)*360, false); // full circle context.stroke(); context.closePath(); </script> </body> </html>