xsleft.blogg.se - Paciello colour contrast analyser

#PACIELLO COLOUR CONTRAST ANALYSER SOFTWARE#

#PACIELLO COLOUR CONTRAST ANALYSER SOFTWARE#

Henny is a Director at TetraLogical and a user experience and digital accessibility specialist with almost 20 years’ experience.įormerly at the BBC, The Paciello Group, Opera Software and RNIB Henny is in her element working with multi-disciplinary teams to help infuse inclusion in each step in the Software Development Lifecycle.

ID24: Rethinking color contrast by Jared Smithįor more information about the Web Content Accessibility Guidelines, read our WCAG primer.

WCAG 2.1 Success Criterion 1.4.11 Non-text Contrast (Level AA).

WCAG 2.1 Success Criterion 1.4.3 Contrast (Minimum) (Level AA).

Always try and exceed the colour contrast minimum, not just meet it.

View your content on a mobile when outside to see if it is still readable in different light conditions.

Text which is part of a logo or brand identity.

A decorative graphic that does not have any meaning or purpose.

An image of text that is not essential to understanding the meaning of the content.There are some types of content that don't need to meet colour contrast requirements: The contrast of the white (#FFFFFF) against the light gray (#DADBDA) outline is just 1.4:1.

Typical example of form fields with bad contrast on the input outline. This includes form fields, links and buttons, and any visual cues that indicate their state.

Small text (less than 24px, except for the bold rule outlined above) should have a minimum contrast ratio of 4.5:1Ĭontrast rules for graphics and user interface componentsĪ contrast ratio of 3:1 is required for graphics containing information needed to understand the content and interactive elements.

Large text (at least 24px, or bold and at least 19px) should have a minimum contrast ratio of 3:1.

There are two contrast requirements for text: The contrast of the white (#FFFFFF) "Submit" text against the dark gray (#222222) background is 15.9:1. Typical example of a button with good contrast. The contrast of the white (#FFFFFF) "Submit" text against the light gray (#CCCCCC) background is just 1.6:1. Typical example of a button with bad contrast.

For example, the colour of a button must contrast clearly against its background, and the button's text label must also contrast well against the button's colour. In some cases, it's necessary to think about more than one contrast ratio per element. It's written as object:background - for example 4.5:1. People with low vision can find text on a patterned or textured background difficult to readĪ colour contrast ratio describes the colour of an object (such as text) against the colour of its background.People with Dyslexia can find text on a pure white background dazzling and difficult to read.People with Autistic Spectrum Disorders can be sensitive to sensory information including very bright or high-contrasting colours.Bright conditions, such as sunlight, can reduce someone's ability to see what's on the screen clearlyĪnother consideration is the psychological impact colours can have on some people:.Differences in device size, resolution and contrast can all affect colour quality.Ageing impacts people's ability to see colours.

Colour Vision Deficiency, otherwise known as colour-blindness, means some people have difficulty recognising certain colours or any colours at all.People find it difficult to read content for many reasons: This is particularly important for people who have conditions that affect vision or colour perception, as well as people browsing on mobile in different light conditions. Good contrast is about using colours that provide enough variation between the content and background.