Color
#1f309e
#1f309ergb(31, 48, 158)hsl(232, 67%, 37%)oklch(0.379 0.177 268.7)Colors that go with #1f309e
Charcoal, Steel Blue and 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.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #1f309e: softer than #000 and cool enough to feel like part of the same palette.
Steel Blue #4682b4
analogousshippedSteel Blue is #1f309e's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Blue #0000ff
shipped6 real palettes, including Procter & Gamble's brand system and CVS's brand system put Blue beside #1f309e, as the supporting colour.
Crimson #dc143c
shippedCrimson is paired with #1f309e in 9 real palettes, including Pepsi's brand system and Walgreens's brand system, as the supporting colour.
Denim #1560bd
shippedDesigners have shipped Denim with #1f309e: 8 real palettes, including Warbyparker's brand system and Unilever's brand system, as the accent.
Firebrick #b22222
shippedDesigners have shipped Firebrick with #1f309e: 4 real palettes, including 3M's brand system and MLB's brand system, as the supporting colour.
Orange Red #ff4500
shippedOrange Red is paired with #1f309e in 4 real palettes, including Tide's brand system and NASA's brand system, as the accent.
Red #ff0000
shippedRed is paired with #1f309e in 4 real palettes, including Walgreens's brand system and 3M's brand system, as the supporting colour.
Real palettes that use #1f309e
Tints & shades
Harmonies
Contrast
| #1f309e as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 10.63:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.97:1 | 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 #1f309e as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Fonts for this mood
#1f309e 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 #1f309e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/1f309e-9c9dc4-df864e-231f2d-e9eef1?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