If more people can see and read your website, ads, information, product sheets and marketing material, then more people can buy your product.
Better visibility and readability means more people can be customers, which equals more revenue.
It's really that simple.
of homepages have low-contrast text
Low-contrast text is the single most common accessibility failure on the web, and has been for six consecutive years of independent testing. If your text does not stand out clearly from its background, a significant portion of your audience cannot read it comfortably — and many cannot read it at all.
of websites fail at least one detectable accessibility check
WCAG sets out clear, testable standards for contrast. Nearly all websites fall short of them. Most are not failing obscure edge cases; they are failing the basics, and low contrast is consistently at the top of the list.
people in the UK have colour blindness
Colour blindness does not only affect colour perception. It frequently reduces contrast sensitivity too, particularly with red and green combinations. Text that appears clearly distinct to a designer may appear flat or washed out to a significant portion of the audience reading it.
people in the UK live with some form of sight loss
Conditions including glaucoma, cataracts, and macular degeneration reduce the eye's ability to distinguish contrast. A colour combination that passes the AA minimum at 4.5:1 can still be genuinely inaccessible for someone in this group. The minimum is not the same as the functional threshold.
of global web traffic comes from mobile devices
Most people reading your content are not at a desk, on a calibrated monitor, in controlled lighting. They are on a phone, outdoors, in variable light. Contrast ratios that look acceptable in a design tool degrade significantly on cheaper screens and in direct sunlight. 7:1 holds up where 4.5:1 does not.
is the WCAG AAA contrast standard. Most tools stop at 4.5:1.
701 is built around the higher threshold. Not because AA is wrong, but because AA was designed as a floor, not a ceiling. Real reading conditions, real screens, and real visual variation all erode contrast. Starting at 7:1 means you still have margin when conditions are not ideal — which, for most users on most devices, they are not.
What each colour signals, and where its contrast trade-offs sit.
High arousal, high attention, high risk if overused
Red is one of the most physiologically active colours. Research consistently associates it with urgency, energy, and elevated alertness. It performs strongly in calls to action, error states, and contexts where an immediate response is the goal. Used precisely, it directs the eye. Used throughout a design, it creates fatigue. On dark backgrounds, red text frequently fails contrast checks, particularly for users with red-green colour vision deficiency.
The most trusted colour across genders and cultures
In one study, blue triggered associations with trust in 74% of participants and competence in 68%. It is the dominant choice in financial services, healthcare, and technology for that reason: it reduces perceived risk. Lighter shades read as open and approachable; darker shades carry authority. As a background or text colour, blue also supports strong contrast ratios when paired correctly, particularly with white or off-white.
The colour the brain reads as safe to proceed
Green's association with nature, growth, and permission is consistent across cultures. It lends itself to wellness, sustainability, finance (particularly savings and positive outcomes), and any context where calm reassurance is the message. Mid-range greens used as backgrounds can be difficult to pair for contrast, but darker greens against white, or white text on deep green, reliably achieve AAA.
The first colour perceived by the retina — and the hardest to pair accessibly
Yellow communicates optimism, energy, and warmth, and it is highly effective at capturing attention quickly. Its significant limitation in digital design is contrast. White text on yellow almost never passes AA, let alone AAA. Black or very dark text is almost always required to make yellow usable. Bright yellow used extensively as a background causes visual fatigue, particularly for users with photosensitivity.
Energy without aggression
Orange occupies the space between red's urgency and yellow's warmth. It communicates enthusiasm, creativity, and approachability, which makes it a strong choice for consumer brands that want to feel active without feeling intense. It performs well in calls to action where warmth matters more than urgency. Like yellow, it requires careful contrast management: white text on orange rarely achieves AA, and black text is the safer pairing in almost all cases.
Luxury, imagination, and creative authority
Purple's associations with royalty, rarity, and premium positioning are consistent across centuries of use and well-documented in consumer research. It lends itself to luxury brands, creative industries, and wellness contexts. Lighter purples, such as lavender, carry romantic and calm associations; deeper purples carry weight and authority. Dark purple text on white backgrounds achieves strong contrast ratios and reads as considered and intentional.
The highest contrast ratio available — and what that means in practice
Black communicates sophistication, precision, and strength. It is the natural choice for premium and minimalist positioning. It is also, practically speaking, the text colour that delivers the highest contrast ratio against white backgrounds, achieving 21:1, which is three times the AAA threshold. Every decision to use a softer or branded text colour involves trading some of that legibility. That trade-off is worth understanding before making it.
The background that makes everything else possible
White signals clarity, openness, and simplicity. It is the most common background colour in digital design, and the one against which the highest contrast ratios are achievable. It reduces visual noise and creates the conditions for other colours to communicate clearly. White text on dark backgrounds can also achieve excellent contrast, though it requires darker base colours than many designers initially assume.
Versatile and professional, with a significant contrast risk
Grey signals balance, neutrality, and understatement. It is widely used in body copy, UI elements, and supporting text. Its risk is substantial: mid-range greys are the single most common source of contrast failures on the web. A grey that looks perfectly readable on a calibrated desktop monitor in a studio frequently fails on a cheaper screen, in bright light, or for a user with any degree of visual impairment. If grey text is part of your palette, test it rigorously.