Color

#311ff4

#311ff4
hex#311ff4
rgbrgb(49, 31, 244)
hslhsl(245, 91%, 54%)
oklchoklch(0.466 0.284 270.5)
Closest name: Bluebonnet (#1c1cf0)Relative luminance 0.0816

Colors that go with #311ff4

Charcoal, Cobalt Blue and Cornflower Blue 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#e3f41f

#1f78f4 · #9b1ff4

#f4311f · #1ff431

Split-complementary

Open in tool →

#f49b1f · #78f41f

#f41f78 · #e3f41f · #1ff49b

Contrast

#311ff4 as textRatioAAAA largeAAAFix
Aaon white
7.98:1passpasspassPasses AAA — no fix needed.
Aaon black
2.63:1failfailfail
  • AA: use #6b5ef7 as the text (4.57:1)
  • AAA: use #938af9 as the text (7.24:1)
  • AA: or shift the background to #c4c4c4 (4.57:1)
  • AAA: or shift the background to #f2f2f2 (7.12:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #311ff4 as the background.

Brands using this color

Fonts for this mood

#311ff4 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #311ff4
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 #311ff4 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/311ff4-a49cc4-dfa54e-261f2d-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