Color

#121e81

#121e81
hex#121e81
rgbrgb(18, 30, 129)
hslhsl(234, 76%, 29%)
oklchoklch(0.312 0.163 268.1)
Closest name: midnightblue (#191970)Relative luminance 0.0264

Colors that go with #121e81

Steel Blue, Charcoal and Cobalt 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 →

#827712

#125582 · #3f1282

#82121d · #1d8212

Split-complementary

Open in tool →

#823f12 · #558212

#821255 · #827712 · #12823f

Contrast

#121e81 as textRatioAAAA largeAAAFix
Aaon white
13.74:1passpasspassPasses AAA — no fix needed.
Aaon black
1.53:1failfailfail
  • AA: use #5967e8 as the text (4.53:1)
  • AAA: use #8690ee as the text (7.24:1)
  • AA: or shift the background to #949494 (4.53:1)
  • AAA: or shift the background to #bababa (7.08:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #121e81 as the background.

Brands using this color

Fonts for this mood

#121e81 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #121e81
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 #121e81 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/121e81-9d9cc4-df8a4e-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