Contrast: why it matters on public-sector websites
Contrast is the visual difference between two colours placed next to each other, usually between text and background. The clearer this difference, the easier it is for different visitors to read, understand and use the content. In digital services, contrast is not just a matter of aesthetics – it is directly linked to accessibility, usability and compliance with requirements.
For public-sector organisations such as municipalities, schools, libraries, museums or other public bodies, sufficient contrast is especially important. These organisations’ websites are used by very different people: older residents, people with visual impairments, people browsing on a phone in bright sunlight, as well as visitors who simply want to find information about services, registration or documents quickly. If text is difficult to read, not only the user experience suffers, but also the organisation’s ability to communicate clearly.
Contrast and WCAG requirements
Under the WCAG 2.1 AA guidelines, the minimum contrast ratio for normal text is 4.5:1, and for larger text 3:1. This means that the text colour must differ clearly enough from the background for the content to be readable for most users. These requirements apply not only to the main page text, but also to buttons, links, form fields, error messages and other parts of the interface.
In practice, this means design decisions should be checked not “by eye” but against clear accessibility criteria. For example, light grey text on a white background may look modern, but in real use it often becomes difficult to read. On public-sector websites, such a choice may conflict with accessibility principles and make information harder to access for residents.
Common contrast mistakes
- Text that is too light on a light background. This is one of the most common problems, especially when aiming for a “light” and minimalist design. Such text can be hard to see not only for people with visual impairments, but for any user reading on a smaller screen or in poorer lighting conditions.
- Using colour as the only way to convey information. If an error in a form is marked only in red, some users may not notice it or understand it. That is why it is important to use additional cues as well: clear text, icons, highlighting or other visual indicators.
- Links and buttons that do not stand out enough. If a link barely differs from plain text, it is difficult for visitors to tell where they can click. This is especially important on municipality or school websites, where users often look for specific actions – registration, application forms or contact details.
- Not checking contrast on mobile devices. Colours that look good on a large monitor may be less visible on a phone. Since a large share of residents access public services on mobile devices, contrast should be assessed on different screens.
Why this matters for organisations
Sufficient contrast helps ensure that website content is accessible to as wide an audience as possible. This is especially relevant for organisations that publish important information about services, deadlines, admissions, events, public tenders or news for residents. If a person cannot read the content comfortably, the organisation is, in effect, not reaching its communication goal.
Accessibility is also linked to overall trust in digital services. Clearly visible text, understandable buttons and easy-to-use forms create a professional, orderly and reliable impression. This matters for a municipality’s resident services page, a library events calendar and a museum ticket information page alike.
Contrast, accessibility and compliance
On public-sector websites, contrast is one of the basic conditions for digital accessibility. It matters not only for better usability, but also for compliance with applicable standards and good practice. When creating or updating a website, it is worth treating contrast as an integral part of the project, not as a final design check.
Although contrast is not directly a GDPR issue, it is closely related to the safe and clear use of digital services. If a user cannot read form fields, consent text or privacy information, there is a risk they will not understand what data they are providing or under what conditions. Clear, readable design therefore also contributes to more transparent information about the processing of personal data.
How to ensure good contrast
Best practice is to check contrast during the design stage and review it again before launching the website. It is important to review not only the main pages, but also all important points in the user journey: search, forms, login windows, document lists, news cards and error messages. This helps avoid situations where only the home page is accessible, while the rest of the system becomes difficult to use.
For public-sector organisations, it is worth choosing colour combinations that are not only visually appealing but also practical. Dark text on a light background is usually the safest and most universal solution. If the organisation’s brand colours are used, they should be adapted so that they do not conflict with accessibility requirements.
In short, contrast is one of the most important foundations of good digital content. It determines whether a municipality, school, museum or library website will be clear, convenient and accessible to all visitors. Well-chosen contrast helps not only to meet requirements, but also to create better public digital services.
Are you creating or updating a public-sector website? Tobalt ensures that website development and accessibility adaptation (WCAG) meet accessibility requirements from the outset.
Want to know whether your website meets WCAG requirements? Get a free accessibility and contrast report — Tobalt will check your website and provide concrete suggestions to ensure compliance.