Glacier
Open in tool →Three blues from ice to deep water on a pale surface — a monochromatic winter set with real depth.
Color
#183d81
#183d81
hex
#183d81rgb
rgb(24, 61, 129)hsl
hsl(219, 69%, 30%)oklch
oklch(0.376 0.123 261.3)Closest name: Deep Space Royal (#223382)Relative luminance 0.0512
Colors that go with #183d81
Steel Blue, Blue and Crimson lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.
Steel Blue #4682b4
analogousshippedSteel Blue is #183d81's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Blue #0000ff
shipped5 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #183d81, as the accent.
Crimson #dc143c
shippedCrimson is paired with #183d81 in 9 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #183d81: 17 real palettes, including Hasbro's brand system and Unilever's brand system, as the supporting colour.
Orange Red #ff4500
shippedOrange Red is paired with #183d81 in 5 real palettes, including NASA's brand system and Tide's brand system, as the supporting colour.
Powder Blue #b0e0e6
shippedDesigners have shipped Powder Blue with #183d81: 4 real palettes, including Glacier and First Snow, as the supporting colour.
Royal Blue #4169e1
shippedRoyal Blue is paired with #183d81 in 11 real palettes, including Nokia's brand system and Confluent's brand system, as the supporting colour.
White Smoke #f5f5f5
neutralWhite Smoke is the surface for #183d81: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy.
Real palettes that use #183d81
Tints & shades
Harmonies
Contrast
| #183d81 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 10.38:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 2.02:1 | fail | fail | fail |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #183d81 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
Sapphire & Gold
Open in tool →Deep sapphire and gold with a teal — old-money jewel tones on an ivory ground; heraldic without a crest.
Fonts for this mood
#183d81 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #183d81
live endpointPoint any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #183d81 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/183d81-9ca5c4-df664e-211f2d-e9f0f1?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md