The readonly ImageData.height property returns the number of rows in the image data object. Syntax imagedata.height Example var imagedata = new ImageData(100, 100); imagedata.height; // 100 Specification Specification Status Comment WHATWG HTML Living StandardThe definition of 'ImageData.height' in that specification. Living Standard Initial definition. Browser compatibility Desktop Mobile Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari Basic support (Yes) 14 (14) 9.0 9.0 3.1 Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android Basic support (Yes) (Yes) 14.0 (14) (Yes) (Yes) (Yes) (Yes) See also ImageData.width