Color

#517efb

#517efb
hex#517efb
rgbrgb(81, 126, 251)
hslhsl(224, 96%, 65%)
oklchoklch(0.627 0.193 266.1)
Closest name: Blue Öyster Cult (#5577ee)Relative luminance 0.2364

Tints & shades

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

Harmonies

Complementary

Open in tool →

#fbce50

#50d3fb · #7850fb

#fb507e · #7efb50

Split-complementary

Open in tool →

#fb7850 · #d3fb50

#fb50d3 · #fbce50 · #50fb78

Contrast

#517efb as textRatioAAAA largeAAAFix
Aaon white
3.67:1failpassfail
  • AA: use #376bfb as the text (4.51:1)
  • AAA: use #0542eb as the text (7.03:1)
  • AA: or shift the background to #1c1c1c (4.65:1)
Aaon black
5.73:1passpassfail
  • AAA: use #6e94fc as the text (7.3:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #517efb as the background.

Brands using this color

Fonts for this mood

#517efb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #517efb
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #517efb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/517efb-9ca2c4-df724e-221f2d-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