Color

#151b6a

#151b6a
hex#151b6a
rgbrgb(21, 27, 106)
hslhsl(236, 67%, 25%)
oklchoklch(0.282 0.134 270.9)
Closest name: midnightblue (#191970)Relative luminance 0.0198

Colors that go with #151b6a

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 →

#6a6515

#15456a · #3a156a

#6a151b · #1b6a15

Split-complementary

Open in tool →

#6a3a15 · #456a15

#6a1545 · #6a6515 · #156a3a

Contrast

#151b6a as textRatioAAAA largeAAAFix
Aaon white
15.03:1passpasspassPasses AAA — no fix needed.
Aaon black
1.4:1failfailfail
  • AA: use #616ae0 as the text (4.65:1)
  • AAA: use #888ee7 as the text (7.07:1)
  • AA: or shift the background to #8f8f8f (4.65:1)
  • AAA: or shift the background to #b3b3b3 (7.17:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #151b6a as the background.

Brands using this color

Fonts for this mood

#151b6a reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #151b6a
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 #151b6a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/151b6a-9e9cc4-df8f4e-241f2d-e9eef1?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