Color

#403bde

#403bde
hex#403bde
rgbrgb(64, 59, 222)
hslhsl(242, 71%, 55%)
oklchoklch(0.479 0.236 274.2)
Closest name: Blurple (#5539cc)Relative luminance 0.0949

Colors that go with #403bde

Charcoal, Sea Green and Amber 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.

Real palettes that use #403bde

Tints & shades

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

Harmonies

Complementary

Open in tool →

#d8de3b

#3b87de · #923bde

#de403b · #3bde40

Split-complementary

Open in tool →

#de923b · #87de3b

#de3b87 · #d8de3b · #3bde92

Contrast

#403bde as textRatioAAAA largeAAAFix
Aaon white
7.25:1passpasspassPasses AAA — no fix needed.
Aaon black
2.9:1failfailfail
  • AA: use #6b66e5 as the text (4.66:1)
  • AAA: use #918eec as the text (7.28:1)
  • AA: or shift the background to #cccccc (4.51:1)
  • AAA: or shift the background to #fcfcfc (7.06:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #403bde 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

#403bde reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #403bde
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 #403bde and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/403bde-a29cc4-df9e4e-261f2d-e9edf1?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