Color

#00378a

#00378a
hex#00378a
rgbrgb(0, 55, 138)
hslhsl(216, 100%, 27%)
oklchoklch(0.364 0.148 259.9)
Closest name: Deep Space Royal (#223382)Relative luminance 0.0457

Tints & shades

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

Harmonies

Complementary

Open in tool →

#8a5300

#007c8a · #0e008a

#8a0037 · #378a00

Split-complementary

Open in tool →

#8a0e00 · #7c8a00

#8a007c · #8a5300 · #008a0e

Contrast

#00378a as textRatioAAAA largeAAAFix
Aaon white
10.97:1passpasspassPasses AAA — no fix needed.
Aaon black
1.91:1failfailfail
  • AA: use #0a6cff as the text (4.6:1)
  • AAA: use #5297ff as the text (7.23:1)
  • AA: or shift the background to #a6a6a6 (4.51:1)
  • AAA: or shift the background to #cfcfcf (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 #00378a as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#00378a reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #00378a
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

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

analyze #00378a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/00378a-9ca7c4-df5f4e-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