Darrin Jenkins / Alamy

When and how to upsize an image

Sometimes you might find the perfect image for your project but the file size is just a little bit too small. So, what do you do? Here’s a quick guide to upsizing the image (this is also known as ‘interpolation’).

When to upsize an image:

  •  If the maximum image size is not big enough for your project

Tips on upsizing your image:

  • Check your image at it’s full size (100%) before and after resizing so you know what you’re working with
  • Don’t try and upsize the image beyond its capabilities, each image will have different capabilities based on a variety of things including the camera used, its file size and any post production work that’s been done. (There’s more info on how to spot if you’ve gone too far a bit later)
  • We recommend using Photoshop to upsize your image, although there are other tools out there

How to upsize in Photoshop:

  1. Open your image in Photoshop and check it at 100% so you can understand the quality of the image before upsizing
  2. Select image from the top menu and choose image size from the dropdown
  3. Make sure the ‘resample’ box is ticked and bicubic is selected
  4. Change the size of the image to the pixel dimensions (final size) you need
  5. Check the image at 100% to check quality hasn’t been compromised

You’ll be able to see if you’ve upsized an image too much because you’ll see the image quality change, you might start to see interpolation artefacts in the image, like squares or ‘jaggies’ where the pixels have been stretched. You can see some examples of what we mean here.

Sometimes you’ll find that upsizing your image isn’t possible and you’ll have to find an alternative. Here are some tips for finding larger files on Alamy:

  • Use the minimum file size filter to the left of the page in search results
  • If you’re looking for more of an illustration style, search using the vectors filter, as they are infinitely scalable (you can make them as big as you need them without altering the quality)

Useful links:

Catch up with the basics of image sizing on Adobe TV, we recommend this short video about resizing and resampling.

Read our other blogs about file sizes: The one thing every designer needs to know about buying images and Choosing the right file size for your image.