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Part of: Clear language

Low literacy users

Last updated: 24 February, 2021

Following this helps people with:

  • low literacy: not comprehending information may decrease quality of life

You’re very likely to have low literacy users reading your digital content. On this page we give some information about low literacy and its affects, then provide guidelines for making content more inclusive for this type of user. Go straight to our low literacy guidelines.

Literacy definition

The definition of literacy by UNESCO, the United Nations Educational, Scientific and Cultural Organization, is:

“Percentage of the population aged 15 years and over who can both read and write with understanding a short, simple statement on their everyday life. Generally, ‘literacy’ also encompasses ‘numeracy’, the ability to make simple arithmetic calculations.”

There are different levels of literacy. When we talk about “very low literacy” on this wiki, we mean people who in general ‘can only understand a short, simple statement about their own life’. Imagine the gap between understanding a short, simple statement about your everyday life and trying to choose a mobile phone, or comprehend the probate process, online.

The term “Low literacy” on this wiki refers to people who can read and understand more than that, but need things to be expressed very simply and clearly.


14% of people in the world aged over 15 years are not literate at all.


1 in 6 adults in England, 7.1 million people, have very low literacy skills as defined by the UK National Literacy Trust. That’s 16.4% of the population. 1 in 4 adults in Scotland, 1 in 8 in Wales and 1 in 5 in Northern Ireland, experience challenges because of low literacy.

And around 10% of the UK population has some level of dyslexia, which makes reading more challenging. Nearly 50% of people in UK prisons have a literacy level below or only just at what is needed for successful employment, many can't read at all.


In America, 43% of the population has low literacy as defined by the US Department of Education's National Assessment of Adult Literacy.


In Australia, 14.1 per cent of the population have very low levels of literacy. Over 40% have literacy levels below what is considered enough to get by in everyday life.

For Aboriginal and Torres Strait Islander peoples, the illiteracy level is even higher, with 40% to 65% defined as functionally illiterate by the Information Access Group.

Literacy and deaf users

Deaf users may well have English as a second, or third language, and may not have a high level of literacy. They may learn to read after becoming fluent in one or more signing language. Consider this when you aim to create accessible content.

Literacy and users with learning disabilities

80% to 90% of students with learning disabilities experience significant difficulty reading.

How low literacy levels affect people

A low level of literacy can negatively affect:

  • career opportunities,

  • social status,

  • health knowledge,

  • feelings of inclusion.

It can cause low self-esteem and frustration, and can be a cause of violent behaviour. Having a low literacy level can increase the chance that someone serves a prison sentence. 

Online reading behaviour

Nielsen Norman Group studies show that:

“lower-literacy users exhibit very different reading behaviors than higher-literacy users: they plow text rather than scan it, and they miss page elements due to a narrower field of view.”

Nielsen Norman researchers also found that when content is revised to be more readable for low-literacy users, high-literacy users found the content more readable too. 


Using clear, relevant language in content design helps with some of the issues low literacy users have. It can:

  • create online content that is inclusive for low literacy users

  • make job advertisements, and job roles themselves, more accessible for applicants with low literacy 

1. Do not rely on readability formulas.

2. Use clear language.

3. Find the words your users are using.

4. Test your content with your users to check if they understand vocabulary in context

5. Make health information very clear.

Usability evidence, including statistics sources 

1. Do not rely on readability formulas. 

They take a small sample of content and make assumptions about the rest of it from that, so they are a guess rather than an analysis. 

They contradict each other. If they were reliable they would all give the same results, as Caroline Jarret and Ginny Redish point out in their article on reasons to avoid readability formulas

Readability formulas do not take context into account and cannot tell you if your users will understand your content. User testing is the only thing that can do that.

2. Use clear language.

You can choose to use simple words and sentence structures instead of complex ones. More users will understand, and it’s quicker to absorb for users who scan content.

For more guidance and studies on plain English, simple sentences and specialist terms visit the clear language section of the wiki.

3. Find the words your users are using.

The UK National Health Services found that users did not know terms like “stool” and changed to using the word “poo”. But sometimes users will know of something, for example a benefit or product, by a more formal term.

Research user language on the online platforms that your users are using, and interview them directly. You might find they use a particular word when chatting to friends and something different on an internet search. Or they may use exactly the same word. That’s a reason why testing is useful.

4. Test your content with your users to check if they understand vocabulary in context. 

Users may or may not know the meaning of a word by itself. Having the context of a sentence and task may improve understanding. Context could also confuse users.

Find out if your users understand words and terms in context. Do they comprehend the meaning you intend to convey? Do they understand the information your content provides? Can they take the right action to successfully complete their task, as a result of reading and understanding informational and instructional content? 

5. Make health information very clear.

Low literacy users can misunderstand language around health, which can be very dangerous for them.

These examples are from Jonathan Berry’s NHS blog post on health literacy:

A patient thought their “positive” cancer diagnosis was a good thing and couldn’t understand why they were not getting better.

A patient sprayed their inhaler on their neck, because they had been told to “spray it on their throat”. Nobody had checked whether they realised they had to open their mouth and inhale.

For more guidance and studies on clear language for health content visit the legal, medical and financial terms wiki page

Usability evidence

7 OECD findings on social mobility, Times Educational Supplement, 2018

Violence against women in relation to literacy and area of residence in Ethiopia, Global Health Action, 2010

The reading plan, The Shannon Trust

Understanding the Gender Gap in Literacy and Language Development, University of Bristol, 2016. PDF format

Writing for lower literacy users, Jakob Nielsen, Nielsen Norman Group, 2005

Lower-Literacy Users: Writing for a Broad Consumer Audience, Jakob Nielsen, Nielsen Norman Group, 2005

Writing content for everyone, R. Strachan, UK Government Digital Service, 2016

Improving Adult Literacy Instruction: Options for Practice and Research, page 182 to 189, Chapter 7, Learning, Reading, and Writing Disabilities, The National Academies Press, 2012

Teaching Children with Autism to Read for Meaning: Challenges and Possibilities, Judi Randi, Tina Newman, and Elena L. Grigorenko, 2011

Literacy, M. Roser and E. Esteban Ortiz-Ospina, Our World in Data, updated 2018

Readability Formulas: 7 Reasons to Avoid Them and What to Do Instead, C. Jarrett and J. Ridish, UX matters, 2019

Does health literacy matter?, blog post, Jonathan Berry, UK National Health Service, 2016

Statistics sources

Adult Literacy in the UK, National Literacy Trust, latest available statistics for adult literacy levels in England: 2012, Scotland: 2009, Wales: 2010 and Northern Ireland: 2012

What do adult literacy levels mean?, National Literacy Trust, 2011

Reading and Dyslexia in Deaf Children, PDF 1.8MB, Dr R. Herman, Professor P. Roy, Dr F. Kyle, City, University of London, 2017 

Dyslexia, British Dyslexia Association, page undated 

U.S. Department of Education's National Assessment of Adult Literacy, 2003

Literacy levels in Australia, The Information Access Group, 2012

Aboriginal and Torres Strait Islander literacy, The Information Access Group, 2012 or after

4228.0 Programme for the International Assessment of Adult Competencies, Australian Bureau of Statistics, 2011 to 2012.

Relevant wiki page

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