Color

#511bf3

#511bf3
hex#511bf3
rgbrgb(81, 27, 243)
hslhsl(255, 90%, 53%)
oklchoklch(0.482 0.277 279.5)
Closest name: Blustering Blue (#4411ff)Relative luminance 0.09

Tints & shades

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

Harmonies

Complementary

Open in tool →

#bdf31b

#1b51f3 · #bd1bf3

#f3511b · #1bf351

Split-complementary

Open in tool →

#f3bd1b · #51f31b

#f31b51 · #bdf31b · #1bf3bd

Contrast

#511bf3 as textRatioAAAA largeAAAFix
Aaon white
7.5:1passpasspassPasses AAA — no fix needed.
Aaon black
2.8:1failfailfail
  • AA: use #7e55f6 as the text (4.52:1)
  • AAA: use #a386f9 as the text (7.34:1)
  • AA: or shift the background to #c9c9c9 (4.53:1)
  • AAA: or shift the background to #fafafa (7.18:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #511bf3 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

#511bf3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #511bf3
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 #511bf3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/511bf3-ab9cc4-dfbd4e-291f2d-e9ebf1?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