Coastal
Open in tool →Sea-teal, sky and sand — bright without shouting; works for travel, wellness, and anything near water.
Color
#212f3f
#212f3f
hex
#212f3frgb
rgb(33, 47, 63)hsl
hsl(212, 31%, 19%)oklch
oklch(0.3 0.035 252.3)Closest name: Blue Whale (#1e3442)Relative luminance 0.0272
Colors that go with #212f3f
Dark Olive Green, Sienna and Slate Blue 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.
Dark Olive Green #556b2f
split-complementshippedDark Olive Green is a split-complement of #212f3f: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Sienna #a0522d
complementaryshippedSienna sits directly opposite #212f3f on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Slate Blue #6a5acd
analogousshippedSlate Blue is #212f3f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Teal #008080
analogousshippedTeal is #212f3f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Amber #ffbf00
shippedAmber is paired with #212f3f in 10 real palettes, including Beach Hut and McDonald's's brand system, as the supporting colour.
Blue #0000ff
shipped19 real palettes, including Minecraft's brand system and Headspace's brand system put Blue beside #212f3f, as the accent.
Blush Pink #e8b4b8
shipped6 real palettes, including Rain Garden and Blush put Blush Pink beside #212f3f, as the accent.
White Smoke #f5f5f5
neutralWhite Smoke is the surface for #212f3f: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy.
Real palettes that use #212f3f
Tints & shades
Harmonies
Contrast
| #212f3f as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 13.61:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.54:1 | 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 #212f3f as the background.
Brands using this color
Palettes built around it
Harbour
Open in tool →Steel blue and haze with a buoy orange on a pale grey — the maritime palette every port town uses for a reason.
Still Water
Open in tool →Dusty teal and mist with a sand accent — low chroma, low contrast between colours, high contrast for text: the recipe for calm.
Dusty Blue
Open in tool →Dusty blue and mist with a nude accent — the quiet wedding palette; nothing here competes with a photograph.
Fonts for this mood
#212f3f reads as cool, muted, dark. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #212f3f
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 #212f3f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/212f3f-9caac4-df564e-1f202d-e9f1f1?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