Color

#1b5aa1

#1b5aa1
hex#1b5aa1
rgbrgb(27, 90, 161)
hslhsl(212, 71%, 37%)
oklchoklch(0.468 0.131 254.5)
Closest name: Blue Chip (#1d5699)Relative luminance 0.1012

Colors that go with #1b5aa1

Charcoal, Crimson and Sienna 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 →

#a1631b

#1b9da1 · #201ba1

#a11b5a · #5aa11b

Split-complementary

Open in tool →

#a1201b · #9da11b

#a11b9d · #a1631b · #1ba120

Contrast

#1b5aa1 as textRatioAAAA largeAAAFix
Aaon white
6.95:1passpassfail
  • AAA: use #1b579d as the text (7.25:1)
Aaon black
3.02:1failpassfail
  • AA: use #2375d1 as the text (4.54:1)
  • AAA: use #599ae3 as the text (7.16:1)
  • AA: or shift the background to #d1d1d1 (4.55:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1b5aa1 as the background.

Brands using this color

Fonts for this mood

#1b5aa1 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1b5aa1
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 #1b5aa1 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1b5aa1-9caac4-df564e-1f202d-e9f1f1?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