Color

#518ddb

#518ddb
hex#518ddb
rgbrgb(81, 141, 219)
hslhsl(214, 66%, 59%)
oklchoklch(0.638 0.134 255.7)
Closest name: Blue Jay (#5588dd)Relative luminance 0.2591

Colors that go with #518ddb

Charcoal, Copper 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 →

#dba051

#51d2db · #5b51db

#db518d · #8ddb51

Split-complementary

Open in tool →

#db5b51 · #d2db51

#db51d2 · #dba051 · #51db5b

Contrast

#518ddb as textRatioAAAA largeAAAFix
Aaon white
3.4:1failpassfail
  • AA: use #2b74d4 as the text (4.61:1)
  • AAA: use #2158a1 as the text (7.06:1)
  • AA: or shift the background to #242424 (4.57:1)
Aaon black
6.18:1passpassfail
  • AAA: use #6298df as the text (7.08:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #518ddb as the background.

Brands using this color

Fonts for this mood

#518ddb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #518ddb
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 #518ddb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/518ddb-9ca9c4-df5a4e-1f1f2d-e9f0f1?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