Color
#12129b
#12129brgb(18, 18, 155)hsl(240, 79%, 34%)oklch(0.33 0.204 267.7)Colors that go with #12129b
Crimson, Steel Blue and Cobalt 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.
Crimson #dc143c
triadicshippedCrimson completes a triad with #12129b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Steel Blue #4682b4
analogousshippedSteel Blue is #12129b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #12129b: 4 real palettes, including Tide's brand system and Purina Pro Plan's brand system, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #12129b: 5 real palettes, including Bank of America's brand system and Warbyparker's brand system, as the accent.
Royal Blue #4169e1
shippedRoyal Blue is paired with #12129b in 6 real palettes, including Discord's brand system and Nivea's brand system, as the lead colour.
Olive Green #808000
complementaryOlive Green sits directly opposite #12129b on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #12129b: softer than #000 and cool enough to feel like part of the same palette.
Orange Red #ff4500
shippedOrange Red is paired with #12129b in 3 real palettes, including Tide's brand system and Intercom's brand system, as the accent.
Real palettes that use #12129b
Tints & shades
Harmonies
Contrast
| #12129b as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 13.24:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.59:1 | 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 #12129b as the background.
Brands using this color
Fonts for this mood
#12129b reads as cool, vivid, technical. 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 #12129b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/12129b-a19cc4-df994e-251f2d-e9edf1?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