- Success Criterion 1.4.1
- Conformance level A
Heatmap With No Value Labels or Data Table Alternative
1.4.1 — Use of Color
Scenario
Setting
A crowdfunding platform's campaign page
What’s wrong
Heatmaps without value labels or accessible data alternative.
Example
Here's a real case from a crowdfunding platform's campaign page: heatmaps without value labels or accessible data alternative.
Why it matters
People with color-vision deficiency, low vision, or constrained viewing conditions such as strong glare. On a crowdfunding platform's campaign page, this barrier means they can't perceive the control's boundary or state.
How to test
View a heatmap in grayscale: if the values become unreadable and there's no numeric label or accessible data table, it fails.
How to fix
A second visual cue (text, underline, icon, or pattern) must convey the information alongside color.
Outcome
Corrected, a crowdfunding platform's campaign page now lets a visitor see the control's boundary and current state.
Who is affected
People with color-vision deficiency, low vision, or constrained viewing conditions such as strong glare.
Learn more
- Understanding Understanding document (opens in a new tab)
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