Color

#1858fb

#1858fb
hex#1858fb
rgbrgb(24, 88, 251)
hslhsl(223, 97%, 54%)
oklchoklch(0.537 0.249 263.6)
Closest name: Blue Ribbon (#0066ff)Relative luminance 0.1414

Colors that go with #1858fb

Charcoal, Crimson 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#fbbb18

#18cafb · #4918fb

#fb1858 · #58fb18

Split-complementary

Open in tool →

#fb4918 · #cafb18

#fb18ca · #fbbb18 · #18fb49

Contrast

#1858fb as textRatioAAAA largeAAAFix
Aaon white
5.49:1passpassfail
  • AAA: use #0444e7 as the text (7.03:1)
Aaon black
3.83:1failpassfail
  • AA: use #316bfc as the text (4.64:1)
  • AAA: use #6892fd as the text (7.12:1)
  • AA: or shift the background to #ebebeb (4.6:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1858fb as the background.

Brands using this color

Fonts for this mood

#1858fb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1858fb
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 #1858fb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1858fb-9ca3c4-df704e-211f2d-e9eff1?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