Color

#1237bf

#1237bf
hex#1237bf
rgbrgb(18, 55, 191)
hslhsl(227, 83%, 41%)
oklchoklch(0.421 0.214 265.1)
Closest name: Blue Hour (#0034ab)Relative luminance 0.0662

Colors that go with #1237bf

Charcoal, Sea Green and Steel 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.

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#bf9a12

#128ebf · #4312bf

#bf1237 · #37bf12

Split-complementary

Open in tool →

#bf4312 · #8ebf12

#bf128e · #bf9a12 · #12bf43

Contrast

#1237bf as textRatioAAAA largeAAAFix
Aaon white
9.03:1passpasspassPasses AAA — no fix needed.
Aaon black
2.32:1failfailfail
  • AA: use #4469ee as the text (4.5:1)
  • AAA: use #7892f2 as the text (7.19:1)
  • AA: or shift the background to #b8b8b8 (4.55:1)
  • AAA: or shift the background to #e3e3e3 (7.04:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1237bf as the background.

Brands using this color

Fonts for this mood

#1237bf reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1237bf
live endpoint

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.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #1237bf and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1237bf-9ca0c4-df7a4e-221f2d-e9eff1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md