Color
#03121c
#03121crgb(3, 18, 28)hsl(204, 81%, 6%)oklch(0.174 0.031 237.5)Colors that go with #03121c
Charcoal, Royal Blue and Rust 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.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #03121c: softer than #000 and cool enough to feel like part of the same palette.
Royal Blue #4169e1
analogousshippedRoyal Blue is #03121c's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Rust #b7410e
split-complementshippedRust is a split-complement of #03121c: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Sienna #a0522d
complementaryshippedSienna sits directly opposite #03121c on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Teal #008080
analogousshippedTeal is #03121c'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 #03121c in 18 real palettes, including Southwest Airlines's brand system and Lemon Squeezy's brand system, as the accent.
Blue #0000ff
shipped21 real palettes, including Kia's brand system and MongoDB's brand system put Blue beside #03121c, as the accent.
Blue Violet #8a2be2
shippedBlue Violet is paired with #03121c in 10 real palettes, including Twitch's brand system and Prepare your taste buds...'s brand system, as the lead colour.
Real palettes that use #03121c
Tints & shades
Harmonies
Contrast
| #03121c as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 18.97:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.11:1 | 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 #03121c as the background.
Brands using this color
Fonts for this mood
#03121c reads as cool, vivid, dark. The font library is tagged with the same vocabulary:
Point 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.
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
›analyze #03121c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/03121c-9cafc4-df4e5a-1f222d-e9f1f0?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