Color

#124eb5

#124eb5
hex#124eb5
rgbrgb(18, 78, 181)
hslhsl(218, 82%, 39%)
oklchoklch(0.454 0.174 260.8)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0891

Colors that go with #124eb5

Charcoal, Crimson 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 →

#b57912

#129fb5 · #2812b5

#b5124e · #4eb512

Split-complementary

Open in tool →

#b52812 · #9fb512

#b5129f · #b57912 · #12b528

Contrast

#124eb5 as textRatioAAAA largeAAAFix
Aaon white
7.55:1passpasspassPasses AAA — no fix needed.
Aaon black
2.78:1failfailfail
  • AA: use #2a70ea as the text (4.6:1)
  • AAA: use #6195ef as the text (7.05:1)
  • AA: or shift the background to #c9c9c9 (4.56:1)
  • AAA: or shift the background to #f7f7f7 (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 #124eb5 as the background.

Brands using this color

Fonts for this mood

#124eb5 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #124eb5
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 #124eb5 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/124eb5-9ca6c4-df644e-201f2d-e9f0f1?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