how to save canvas as png image

Question

I have a canvas element with a drawing in it  and I want to create a button that when clicked on  it will save the image as a png file  So it should open up the save  open  close dialog box     I do it using this code  var canvas   document getElementById  myCanvas    window open canvas toDataURL  image png       But when I test it out in IE9  a new window opens up saying  the web page cannot be displayed  and the url of it is   data image png base64 iVBORw0KGgoAAAANSUhEUgAAAmAAAABpCAYAAACd 58xAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAADRwSURBVHhe7V0HgBVF0q7ZJSlJwRxAPUFRD39RFLN34qGnnomoqIjhzBlFPROIgsoZzogR5AQEzJ4BPFAUEUwgJjgQkCQKooggaf 6el6 6ZnpSW zUn237u5MdXX1172 z6rqaqeEG6VsJet pDW vkdrfx3H3yfT2tVzaP26X6hkw1q BoeI 280 29JwznZxJPUyXtBQBAQBAQBQaBcECjefmi56BWlZYtAeqajx WokfrJYEqOIikOFRfXoVq161PtOk2odu0t ectqKiojnrntWhC46QhYOtXfUarl79Ivy9 ldau h tX 8b2SbjJ07pWFQy2Uqnp2yXSrQJAoKAICAICALJCAgBS8ao8iTi UvpSZlBxiwqwWOKimsxCWtEdettR3XqbEfFtRonkrBYArZh3fe0 senadWyEbRm1UzasP53K45ZiFc84RKyVXkbVUYWBAQBQUAQyIqAELCsiFW2fDQpSyZk8UQMMysqKmaPWCOqt8mOVK eTuQU1YuccCQBW7dyIq38 j5a fN ad3a5QGXmqsvLfGKJl0ZCFdONEOPyl5lGV8QEAQEAUGghiMgBKzqLHCeHqVOrILtduF4MpZExEqoVq167A3bmjap34J bmoFqcj2dM3Pr9GK b1p5bJXmXz9nEC 3FiorYF4hcmXlo gUrk um  e QoVWfxxRJBQBAQBAQBQUAQqBwE8uzCwiMiaEqOWYR5jJ2 6Hl58nYHk0Pr1v1Ov62cTytXfE5r1yyyc6RgDhjI16 L tLqFZ9xnteGUKc0Xi876YpYkFDCfpqFEz9YGpRERhAQBAQBQaB8ERAPWPnim157JreX6 eK7eJ Ge0RS8oPc9gT1pTqN2jFocltfdPxecBU2HHxgBTky 71CjPGCO YyU4j0TU9ZcGf0y JSAoCgoAgIAgIAoJATUcgG2dQ0jpKZ Xp PlLtEcs3huGQhO r17K3rBvuGrEUt8i5HPAkHC Yt6lKuwYKiuRM9TtGbY0rcerTBLwC KY1fSNJ MTBAQBQUAQqAwExANWGaiHx0z2aJl9CknET MRc2XsVSKKaNP6O1CDhvtwYn5dJZf3gOG0IxLuS0e LB4vw9sVhiwmHywmF6xqLLdYIQgIAoKAICAICAJVAQHTo2XmkNtzv6K5R7RXLOwRs3MaW 47SNkG9oRxZQmun6qbImCo84VSE 5pR3 zvFZJni 7e8tTHiCeqCkAqsKKig2CgCAgCAgCgoAgUG0RCBKzMLmwkzHdL4pk4XlUAn7Uu3XrVtPqVfO4lurPSq0KQa5cdAv9snBgqM5XFPlKSsSPM8o3mcxES2hZtf0rEMMFAUFAEKiBCEgIsqotavpk OiwZViHPQk LgHfHo5EnbCGjVpxeYo9yNmw9oeSn2YeTatWTPNzozzX8ZOeWPJlJVRJnrOoxUtJtmLEUmqoartH7BEEBAFBQBCoJggIASu hUqkUokC2rZkwSSCBU12wpadhNXbpAk13vwwKlJ3O L1QmYrxPNlDxuGyVtyIn6K8KSZHwY3XsRX W0L0VyTEPjwM6KuFxN1uiB6Vkv48MpdjxLt9ieieQvscuvWE13eh2jnQ9zv F2aICAICAKCQGEIRH22559H5IqnDTMGeU SgUJ7WNLjOVH9g8 Xrv2Fa4P9SM6K7y4t WXRw76sfVc42fPV936iJ5 LKrbqTU0P3rA 0dZbEh20L9HJHYj23I2oVrHFT5U5NFnY4m6svUA0Pvo8efbvjCBqtr0nN IVot4Dkvv1v5aoy HJcpUpsfI3olffdknV0uWuJfv9kWjkw55VIFAfM073PE4EkqZbEBf9HMTs8C6e3KhHiPbdqzJnKWMLAoJAeSMgHrDyRrj0 rOEGvVoYY9Y0inIeE YqQ cqGGj3dgDtvJjC mKm7BHmG68lGjO 0T  Anyone know how to fix this

User · Answer

var canvasId   chart id    -canvas   var canvasDownloadId   chart id    -download-canvas   var canvasHtml   Ext String format   lt canvas id   0   width   1   height   2   gt  lt  canvas gt  lt a id   3    gt    canvasId  chart getWidth    chart getHeight    canvasDownloadId   var canvasElement   reportBuilder add   html  canvasHtml      var canvas   document getElementById canvasId    var canvasDownload   document getElementById canvasDownloadId   canvasDownload href   chart getImage   data  canvasDownload download    chart    canvasDownload click

User · Answer

I had this problem and this is the best solution without any external or additional script libraries  In Javascript tags or file create this function  We assume here that canvas is your canvas   function download            var download   document getElementById  download            var image   document getElementById  canvas   toDataURL  image png                        replace  image png    image octet-stream            download setAttribute  href   image            In the body part of your HTML specify the button    lt a id  download  download  image png  gt  lt button type  button  onClick  download    gt Download lt  button gt  lt  a gt    This is working and download link looks like a button  Tested in Firefox and Chrome

User · Answer

FileSaver js should be able to help you here   var canvas   document getElementById  my-canvas       draw to canvas    canvas toBlob function blob        saveAs blob   pretty image png

User · Answer

I maybe discovered a better way for not forcing the user to right click and  save image as   Live draw the canvas base64 code into the href of the link and modify it so the download will start automatically  I don t know if it s universally browser compatible  but it should work with the main new browsers   var canvas   document getElementById  your-canvas        if  canvas getContext            var C   canvas getContext  2d               your-canvas   mousedown function event           feel free to choose your event             just for example        var OFFSET     this  offset           var x   event pageX - OFFSET left         var y   event pageY - OFFSET top          standard data to url     var imgdata   canvas toDataURL  image png           modify the dataUrl so the browser starts downloading it instead of just showing it     var newdata   imgdata replace   data image  png   data application octet-stream           give the link the values it needs        a linkwithnewattr   attr  download   your pic name png   attr  href  newdata          You can wrap the  lt a gt  around anything you want

User · Answer

To accomodate all three points    button save the image as a png file open up the save  open  close dialog box   The file dialog is a setting in the browser   For the button save part assign the following function  boiled down from other answers  to your buttons onclick   function DownloadCanvasAsImage        let downloadLink   document createElement  a        downloadLink setAttribute  download    CanvasAsImage png        let canvas   document getElementById  myCanvas        let dataURL   canvas toDataURL  image png        let url   dataURL replace   data image  png   data application octet-stream        downloadLink setAttribute  href   url       downloadLink click        Example on Codepen  Another  somewhat cleaner  approach is using Canvas toBlob     function DownloadCanvasAsImage        let downloadLink   document createElement  a        downloadLink setAttribute  download    CanvasAsImage png        let canvas   document getElementById  myCanvas        canvas toBlob function blob          let url   URL createObjectURL blob         downloadLink setAttribute  href   url         downloadLink click                Example on Codepen  Neither solution is 100  cross browser compatible  so check the client

User · Answer

Try this   jQuery  body   after   lt a id  Download  target   blank  gt Click Here lt  a gt      var canvas   document getElementById  canvasID    var ctx   canvas getContext  2d     document getElementById  Download   addEventListener  click   function         downloadCanvas this   canvas    test png       false    function downloadCanvas link  canvasId  filename        link href   document getElementById canvasId  toDataURL        link Download   filename      You can just put this code in console in firefox or chrom and after changed your canvas tag ID in this above script and run this script in console   After the execute this code you will see the link as text  click here  at bottom of the html page  click on this link and open the canvas drawing as a PNG image in new window save the image

User · Answer

Full Working HTML Code  Cut Paste into new  HTML file   Contains Two Examples    Canvas in HTML file  Canvas dynamically created with Javascript    Tested In    Chrome Internet Explorer  Edge  title name does not show up  Firefox Opera      lt  DOCTYPE HTML  gt   lt html lang  en  gt   lt head gt       lt meta charset  UTF-8  gt       lt title gt   SAVE CANVAS TEST   lt  title gt       lt meta          name     author           content  John Mark Isaac Madison       gt       lt  -- EMAIL  J4M4I5M7 - AT - Hotmail com -- gt   lt  head gt   lt body gt    lt div id  about the code  gt      Illustrates       lt ol gt       lt li gt How to save a canvas from HTML page       lt  li gt       lt li gt How to save a dynamically created canvas  lt  li gt       lt  ol gt   lt  div gt    lt canvas id  DOM CANVAS           width   300           height  300   gt  lt  canvas gt    lt div id  controls  gt       lt button type  button  style  width 300px               onclick  obj SAVE CANVAS    gt          SAVE CANVAS   Dynamically Made Canvas        lt  button gt        lt button type  button  style  width 300px               onclick  obj SAVE CANVAS  DOM CANVAS    gt          SAVE CANVAS   Canvas In HTML Code        lt  button gt   lt  div gt    lt script gt  var obj   new MyTestCodeClass    function MyTestCodeClass           Publically exposed functions      this SAVE CANVAS   SAVE CANVAS          Private      var  canvas      var  canvas id    ID OF DYNAMIC CANVAS       var  name hash counter   0          Create Canvas       function  constructor            var D     document          var CE    D createElement bind D            canvas   CE  canvas             canvas width   300           canvas height  300           canvas id       canvas id                    Before saving the canvas  fill it so        we can see it  For demonstration of code      function  fillCanvas input canvas  r g b           var ctx   input canvas getContext  2d            var c     input canvas           ctx fillStyle    rgb   r     g     b              ctx fillRect 0  0  c width  c height                 Saves canvas  If optional id supplied         will save canvas off the DOM  If not         will save the dynamically created canvas      function SAVE CANVAS optional id            var c    getCanvas  optional id                Debug Code  Color canvas from DOM            green  internal canvas red          if  optional id                 fillCanvas c 0 255 0            else               fillCanvas c 255 0 0                       saveCanvas  c                  If optional id supplied  get canvas        from DOM  Else  get internal dynamically        created canvas      function  getCanvas  optional id            var c   null     canvas          if  typeof optional id     string                var id   optional id              var  d   document              var c    d getElementById  id             else              c    canvas                     return c             function  saveCanvas  canvas            if  window   alert   WINDOW IS NULL                   We want to give the window a unique            name so that we can save multiple times            without having to close previous            windows           name hash counter                           var NHC    name hash counter                var URL    about blank                      var name   UNIQUE WINDOW ID    NHC          var w window open  URL  name                 if  w   alert   W IS NULL                  Create the page contents             THEN set the tile  Order Matters          var DW                                       DW      lt img src                              DW    canvas toDataURL  image png            DW       alt  from canvas   gt                  w document write DW                          w document title    NHC  NHC                     end class   lt  script gt    lt  body gt   lt  -- In IE  Script cannot be outside of body   -- gt   lt  html gt

User · Answer

try this   var c document getElementById  alpha    var d c toDataURL  image png    var w window open  about blank   image from canvas    w document write   lt img src    d    alt  from canvas   gt       This shows image from canvas on new page  but if you have open popup in new tab setting it shows about blank in address bar   EDIT - though window open   lt img src     c toDataURL  image png        gt    does not work in FF or Chrome  following works though rendering is somewhat different from what is shown on canvas  I think transparency is the issue   window open c toDataURL  image png

User · Answer

I really like Tovask s answer but it doesn t work due to the function having the name download  this answer explains why   I also don t see the point in replacing  data image      with  data application        The following code has been tested in Chrome and Firefox and seems to work fine in both   JavaScript   function prepDownload a  canvas  name        a download   name     a href   canvas toDataURL       HTML    lt a href     onclick  prepDownload this  document getElementById  canvasId     imgName png    gt Download lt  a gt   lt canvas id  canvasId  gt  lt  canvas gt

User · Answer

Submit a form that contains an input with value of canvas toDataURL  image png   e g     JAVASCRIPT      var canvas   document getElementById  canvas        var url   canvas toDataUrl  image png      Insert the value of the url to your hidden input on form element     PHP       data     POST  photo         data   str replace  data image png base64         data        data   base64 decode  data       file put contents  i    rand 0  50    png    data

User · Answer

I used this solution to set the file name   HTML    lt a href     id  downloader  onclick  download    download  image png  gt Download  lt  a gt   lt canvas id  canvas  gt  lt  canvas gt    JavaScript   function download        document getElementById  downloader   download    image png       document getElementById  downloader   href   document getElementById  canvas   toDataURL  image png   replace   data image          data application octet-stream

[javascript] how to save canvas as png image?

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