# Accessibility Heatmap Generator Generate a contrast-focused accessibility heatmap from a UI screenshot or HTML input and suggest stronger patch colors > Canonical page: https://elysiatools.com/en/tools/accessibility-heatmap-generator - **Category:** Design - **Keywords:** accessibility, heatmap, wcag, contrast, ui screenshot, html audit ## Overview Upload a UI screenshot or paste HTML with inline colors, then generate a heatmap that highlights regions likely to fail WCAG contrast thresholds. The tool is designed for quick visual triage before design review or implementation handoff. How it works: - For screenshots, it samples local color tiles, estimates contrast hotspots, and renders a red overlay heatmap. - For HTML, it inspects inline foreground/background pairs and returns low-contrast findings plus suggested patch colors. - WCAG Level controls the threshold: AA uses 4.5:1 and AAA uses 7:1 for normal text. - Show Patch Suggestions adds recommended foreground color values to help lift contrast faster. ## Inputs - **HTML Input** (textarea): Low contrast text - **Design Image** (file) - **WCAG Level** (select) - **Show Patch Suggestions** (checkbox) ## When to use - When reviewing design mockups to catch low-contrast text before handing files off to developers. - When auditing existing HTML components to ensure inline foreground and background colors meet WCAG standards. - When you need quick, actionable color adjustments to fix accessibility failures without manually calculating contrast ratios. ## How it works - Upload a UI screenshot (PNG, JPG, WEBP) or paste an HTML snippet containing inline color styles. - Select your target WCAG compliance level (AA for 4.5:1 or AAA for 7:1) to set the strictness of the contrast check. - Enable 'Show Patch Suggestions' to automatically generate recommended foreground colors that pass the selected threshold. - Download the generated HTML report, which displays a red overlay heatmap on images or lists specific contrast findings for HTML inputs. ## Use cases - Designers validating dashboard mockups to ensure gray text on white backgrounds remains legible for visually impaired users. - Front-end developers testing HTML email templates to verify that inline styles meet accessibility guidelines. - QA testers performing visual accessibility audits on web applications by taking screenshots of various UI states. ## Frequently asked questions ### What image formats are supported? You can upload PNG, JPG, or WEBP images up to 15MB for screenshot analysis. ### What is the difference between WCAG AA and AAA? WCAG AA requires a contrast ratio of at least 4.5:1 for normal text, while AAA is stricter and requires a 7:1 ratio. ### How does the tool analyze HTML? It inspects inline style attributes for foreground and background color pairs, calculates their contrast ratio, and flags those that fail the selected WCAG level. ### What are patch suggestions? If enabled, the tool calculates and recommends a new foreground color that is visually similar but dark or light enough to pass the contrast threshold. ### Can it analyze an entire live website? No, the tool is designed for specific UI screenshots or raw HTML snippets to provide focused, component-level triage. ## Related tools - [PDF Invoice Generator](https://elysiatools.com/en/tools/pdf-invoice-generator): Generate a branded invoice PDF from structured line items - [Data URI Generator](https://elysiatools.com/en/tools/data-uri-generator): Convert files into Data URIs (Base64 or percent-encoded) for inlining images, fonts, and assets directly into HTML, CSS, or Markdown - [Depth Map Generator](https://elysiatools.com/en/tools/image-depth-map): Generate depth maps from images using brightness, saturation, and edge analysis. Creates grayscale depth maps where lighter pixels indicate closer objects and darker pixels indicate further objects. - [Parallax Animation Generator](https://elysiatools.com/en/tools/image-parallax): Generate parallax animations from images. 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