#666f8a as text	Ratio	AA	AA large	AAA	Fix
Aaon white	4.99:1	pass	pass	fail	AAA: use #50576d as the text (7.18:1)
Aaon black	4.21:1	fail	pass	fail	AA: use #6a7490 as the text (4.51:1) AAA: use #9097ad as the text (7.22:1) AA: or shift the background to #f5f5f5 (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #666f8a as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Palettes built around it

0f172a 64748b 2563eb f8fafc

Slate Workspace

Open in tool →

Slate on slate with a single blue — the productivity-app look where the interface disappears behind the work.

Minimal Cool Clean ModernSaas

0e7490 64748b f97316 f8fafc 0f172a

Clinic

Open in tool →

Teal reads clinical without the coldness of pure blue; the coral accent adds warmth for reassurance moments.

Clean Cool LightHealth

1d4ed8 64748b f59e0b ffffff 1e293b

Campus

Open in tool →

Institutional blue with a highlighter-amber accent — trustworthy for parents, lively enough for students.

Friendly Cool CleanEducation

mcpConnect your agent — build around #666f8a

live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp

claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp

try this prompt

›analyze #666f8a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/666f8a-9ca1c4-df754e-221f2d-e9eff1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md