Color

#331fa3

#331fa3
hex#331fa3
rgbrgb(51, 31, 163)
hslhsl(249, 68%, 38%)
oklchoklch(0.372 0.195 278)
Closest name: Depths of Night (#2c319b)Relative luminance 0.0433

Tints & shades

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

Harmonies

Complementary

Open in tool →

#8fa31f

#1f4da3 · #751fa3

#a3331f · #1fa333

Split-complementary

Open in tool →

#a3751f · #4da31f

#a31f4d · #8fa31f · #1fa375

Contrast

#331fa3 as textRatioAAAA largeAAAFix
Aaon white
11.26:1passpasspassPasses AAA — no fix needed.
Aaon black
1.87:1failfailfail
  • AA: use #7460e1 as the text (4.5:1)
  • AAA: use #998be9 as the text (7.22:1)
  • AA: or shift the background to #a6a6a6 (4.62:1)
  • AAA: or shift the background to #cccccc (7.01:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #331fa3 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

#331fa3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #331fa3
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 #331fa3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/331fa3-a79cc4-dfae4e-271f2d-e9ecf1?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