Photoshop

Change pixel dimensions of an image

Changing an image’s pixel dimensions affects not only its on‑screen size but also its image quality and its printed characteristics—either its printed dimensions or its image resolution.

  1. Choose Image > Image Size.
  2. To maintain the current ratio of pixel width to pixel height, select Constrain Proportions. This option automatically updates the width as you change the height, and vice versa.
  3. Under Pixel Dimensions, enter values for Width and Height. To enter values as percentages of the current dimensions, choose Percent as the unit of measurement. The new file size for the image appears at the top of the Image Size dialog box, with the old file size in parentheses.
  4. Make sure that Resample Image is selected, and choose an interpolation method.
  5. If your image has layers with styles applied to them, select Scale Styles to scale the effects in the resized image. This option is available only if you selected Constrain Proportions.
  6. When you finish setting options, click OK.
    For best results when you produce a smaller image, downsample and apply the Unsharp Mask filter. To produce a larger image, rescan the image at a higher resolution.