Color

#378bc3

#378bc3
hex#378bc3
rgbrgb(55, 139, 195)
hslhsl(204, 56%, 49%)
oklchoklch(0.611 0.117 241.7)
Closest name: steelblue (#4682b4)Relative luminance 0.2322

Tints & shades

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

Harmonies

Complementary

Open in tool →

#c36f37

#37c3b5 · #3745c3

#c3378b · #8bc337

Split-complementary

Open in tool →

#c33745 · #c3b537

#b537c3 · #c36f37 · #45c337

Contrast

#378bc3 as textRatioAAAA largeAAAFix
Aaon white
3.72:1failpassfail
  • AA: use #307aab as the text (4.67:1)
  • AAA: use #245b7f as the text (7.3:1)
  • AA: or shift the background to #1c1c1c (4.58:1)
Aaon black
5.64:1passpassfail
  • AAA: use #549ecf as the text (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 #378bc3 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

#378bc3 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #378bc3
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 #378bc3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/378bc3-9cafc4-df4e5a-1f222d-e9f1f0?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