Image Source / Alamy

Which image file type do I need?

With so many different image file types around, it can be hard to understand which one you need when you’re new to image buying. There’s  GIF, PNG, JPEG and that’s just the beginning.

So what do you need to know to pick the right file type for your project? Here’s a quick breakdown of some of the most frequently used images file types and when to use them.


JPEG is one of the most used formats when it comes to digital images, especially for web use. They’re perfect for digital photographs because each file can incorporate 16.8 million colours.

JPEG files can be saved at a variety of quality levels – which is great if you need a smaller file size. The lower the quality you save it at, the higher the compression rate – so if you need a smaller size you should save it at a lower quality.

If you need to use the image for a large format project, like a billboard, be aware that upsizing a compressed image could affect the quality. You’ll need to think about your final project when choosing your quality level and compression rate.  To find out more about upsizing an image go to our blog when and how to upsize an image.

Great for – digital photos
Not so good for – logos or animations


A  GIF is often used for images that have large blocks of colour rather than a lot of detail. It will only display up to 256 colours compared to the 16.8million in a JPEG file. This means it is great for logos and icons, but not so good for digital photographs.  If you need to make your file smaller you can reduce the number of colours being used – the maximum is 256 and the minimum is 2.

With a GIF file you can make the background transparent, making it ideal for logos because you can place them over other images or on web pages, without worrying about the background colour.

Great for – logos and icons
Not so good for – digital photos or images with lots of colours


The great thing about a PNG file is that when it’s compressed it doesn’t affect the overall quality of the image (unlike JPEGs), but PNG files are larger than JPEG files, especially when they’re high resolution, which makes them harder to share and use. PNG files aren’t supported by all web browsers either so they aren’t the best choice for websites and blogs.

There are two types of PNG formats: PNG-8 and PNG-24 –

• PNG-8 has a 256 colours maximum but can be made into smaller files
• PNG-24 format can display millions of colours, but also comes with a larger file size

Great for- smaller files and logos
Not so good for – larger images, using on the web

We supply all our images as zipped JPEGS because it makes them quick to download and easy to share. But if you need an alternative file type it’s easy to do.

1. Download the zipped JPEG from Alamy
2. Extract the file
3. Open the image in Photoshop (or another image editing software)
4. File, Save As, and choose the image format you need

For more help with file sizes head over to our blog How to choose the right file size for your project, or visit the file sizes page on our site.