In this paper, we propose the method of converting 2D image to 3D image using linear curves in HTML5. We use only one image without any other information about depth map for creating 3D images. So we filter the original image to extract RGB colors for left and right eyes. After selecting the ready-made control point of linear curves to set up depth values, users can set up the depth values and modify them. Based on the depth values that the end users select, we reflect them. Anaglyph 3D is automatically made with the whole and partial depth information. As all of this work has been designed and implemented in Web environment using HTML5, it is very easy and convenient and end users can create any 3D image that they want to make.