Color

#1237a5

#1237a5
hex#1237a5
rgbrgb(18, 55, 165)
hslhsl(225, 80%, 36%)
oklchoklch(0.394 0.181 264.6)
Closest name: Blue Hour (#0034ab)Relative luminance 0.0558

Colors that go with #1237a5

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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a58112

#1281a5 · #3712a5

#a51237 · #37a512

Split-complementary

Open in tool →

#a53712 · #81a512

#a51281 · #a58112 · #12a537

Contrast

#1237a5 as textRatioAAAA largeAAAFix
Aaon white
9.93:1passpasspassPasses AAA — no fix needed.
Aaon black
2.12:1failfailfail
  • AA: use #436dea as the text (4.61:1)
  • AAA: use #7594f0 as the text (7.25:1)
  • AA: or shift the background to #b0b0b0 (4.58:1)
  • AAA: or shift the background to #d9d9d9 (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1237a5 as the background.

Brands using this color

Fonts for this mood

#1237a5 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1237a5
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 #1237a5 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1237a5-9ca1c4-df754e-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