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The POUR principles

A dad pouring milk on his daughter's cereal

Photo credit: Gabby K

The POUR principles in practice


We often think about perceivable in the sense of seeing. But it really means all of our senses. 

The 5 senses of sight, hearing, touch, taste and smell. Today, we can’t use taste and smell for digital. Maybe one day? 

For now, all the content we make for the web has to be perceivable through sight, hearing or touch. 

People see things on a screen

People hear things through loudspeakers 

People touch words through
a braille display

People see, hear and feel
through a mobile phone

2 way rule

When making content for the web, it’s important to remember the 2 way rule. There must be at least 2 ways to sense the content. Text is easy. People can read text visually. Or assistive technology can read it out for them. 

Images are easy to see, but how can you hear them? Alternative text (alt text) can be written for each image which gives assistive technology something to read in place of the image. More and more we are going to have systems that use voice as an input, like Amazon Alexa, or Google Home.


There are many ways that people can operate the web. Mouse and keyboard are the obvious ones. But there’s also voice recognition. Eye tracking, sip-and-puff, headsticks and switches all help disabled people operate their computers and tablets. 



Voice recognition 

Eye tracking

Head stylus 

Switch control

A good way to make sure that your content is available for each of these input methods is to use your keyboard, and not just a mouse, to navigate the page. 


The content you produce isn’t going to be accessible if people can’t understand it. This comes down to legibility, readability and comprehension. 


Legibility is the ability to see, distinguish, and recognize the characters and words in your text. Typography and visual design are important here. 

Use simple, sans serif fonts. Check out Google fonts for Andika, PT Sans, Sawarabi Mincho, Raleway, Chivo, KoHo or Cabin.

Have a look at the characters I l 1 O 0 b d p q. Can you clearly see the difference between the capital I, the lowercase l and the number 1? If the p and q and b and d are symmetrical they can cause legibility problems too. 

Make sure that color contrast is good. Don’t use light grey text on a white background, for example.   


Readability is the ability to read the words and sentences.

Use ordinary words, short sentences and paragraphs, and the active voice. Write as if you are talking with your reader. 


Comprehension is the ability to understand the meaning of the words. Help comprehension by reducing the mental resources (cognitive load) needed. 

Use language that is familiar to your audience. Start with the main points, and elaborate as needed. Be brief.  

Easy to read 

Easy-to-read information is easier to understand.

Easy-to-read information is important for people with intellectual disabilities.

It is important so they can:

  • Learn new things.
  • Take part in society.
  • Know their rights and stand up for them.
  • Make their own choices.

There are rules how to make easy-to-read

Easy Read Training | Making documents Easy Read

Read Easy - Helping adults learn to read  


This is the principle over which we have least control as a social media comms team. 

One way to understand robust is to think of what a web page looks like on a 32” monitor, a 15” laptop, a 10” tablet, a 6” mobile and a 1” digital watch. What parts of the page need to change, or be removed? 

Each social media platform has a different design for each size of device. It’s important to think about this while we are designing our content. Use the standards of the social media platform for images so that things look right. A guide to design sizes from Canva.com has all the details you need.  

POUR Principles reading list

Accessibility Principles | Web Accessibility Initiative (WAI) | W3C 

Barclays POUR Principles explainer videos

What are the POUR Principles? | Accessibility Explainer 

POUR Principles - Perceivable | Accessibility Explainer

POUR Principles - Operable | Accessibility Explainer 

POUR Principles - Understandable | Accessibility Explainer 

POUR Principles - Robust | Accessibility Explainer

Web content accessibility guidelines (WCAG)

The WCAG are the web standards for accessibility. They are the base level of expectations for the web. They are referenced in accessibility legislation around the world. 

The POUR principles

There are 4 principles in the WCAG, the POUR principles

  • Perceivable
  • Operable
  • Understandable
  • Robust