Named color

Burning Ultrablue

#150aec
hex#150aec
rgbrgb(21, 10, 236)
hslhsl(243, 92%, 48%)
oklchoklch(0.434 0.29 266)
Relative luminance 0.0643

Burning Ultrablue on this page is the real value, not a screenshot: exact hex, RGB, HSL and OKLCH, ten tints and ten shades, classic harmonies, and WCAG contrast with fixes — plus the 35 public brands that use it and the palettes it appears in.

Colors that go with Burning Ultrablue

Charcoal, Crimson and Cobalt 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 →

#e0eb0a

#0a6feb · #860aeb

#eb150a · #0aeb15

Split-complementary

Open in tool →

#eb860a · #6feb0a

#eb0a6f · #e0eb0a · #0aeb86

Contrast

Burning Ultrablue as textRatioAAAA largeAAAFix
Aaon white
9.18:1passpasspassPasses AAA — no fix needed.
Aaon black
2.29:1failfailfail
  • AA: use #6a62f8 as the text (4.72:1)
  • AAA: use #8f89fa as the text (7.13:1)
  • AA: or shift the background to #b8b8b8 (4.63:1)
  • AAA: or shift the background to #e3e3e3 (7.16:1)

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

Brands using this color

Fonts for this mood

Burning Ultrablue reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around Burning Ultrablue
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 #150aec and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/150aec-a39cc4-dfa04e-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