Beginner’s Guide to Image File Formats

Have you ever noticed that graphic files have different extensions? Have you noticed that some graphics are better quality than others? Or that some graphic formats can be uploaded to social media and some cannot? Which raises the question, what’s the best image file format for your situation?

Images on the web can come in many forms – from JPEGs to GIFs. It’s complicated enough that there are so many acronyms you need to remember, never mind sussing out which is the best image file format to use for your needs.

In this blog, we will be discussing why you need to think about what image format you’re going to use and which format you should use for different situations.

What is An Image File Format?

An image file format is a way of displaying graphic information. The formats are either raster or vectors.

Raster: images tend to lose quality when they’re scaled up (JPEG, PNG, GIF)

Vector: are used to create images that may require resizing – like logos and drawn illustrations (SVG)

What Image File Formats Can Affect

Performance: some image formats take up more space than others, which can cause your website speed to slow down

Appearance: some image formats include more detail and are better quality, where as some can be pixilated

Scalability: when you increase or decrease the size of an image too much, the quality is affected, and how the image looks on small and large screens can be impacted too

What Are The Most Popular Image File Formats?

You’ll most likely come across the below four formats:

  1. 1. JPEG
  2. 2. PNG
  3. 3. GIF
  4. 4. SVG

1. JPEG (Joint Photographic Experts Group)

Is a lossy compressed file format. Which makes it useful for storing images at a smaller size because it has minimal impact to page loading times.

JPEG is a common choice for web pages due to its clever balance of file size and image quality.

A JPEG image format should be used in any situation when it’s important to have a small file.

2. PNG(Portable Network Graphics)

Like JPEG, PNG supports millions of colours, but it’s recommended to use PNG for images that contain less colour data.

Its good practise to use PNG when retaining the quality of a detailed image is important and the file size doesn’t particularly matter. You can use PNG for transparent backgrounds or partial transparency.

3. GIF (Graphic Interchange Format)

It’s like PNG when comparing image quality, but you can also create animations for the web with GIF.

There’s less colour range available, so it’s not suitable for all photos – but it’s ideal for icons with few colours.

4. SVG (Scalable Vector Graphics)

Are image formats that are universally supported across all desktop and mobile browsers.

Images can be scaled the same way we scale all other elements in responsive web design and elements inside SVG can be animated to create interactive experienced.

What is The Best Image File Format to Use?

It depends on your situation. Ideally, you will select whatever format enables you to deliver high quality images without slowing down your loading speed times.

Want to store colourful images in the smallest size? Use JPEG. Do you need the images to be high-quality? Use PNG.