Color

#537ef3

#537ef3
hex#537ef3
rgbrgb(83, 126, 243)
hslhsl(224, 87%, 64%)
oklchoklch(0.623 0.182 266.1)
Closest name: Blue Öyster Cult (#5577ee)Relative luminance 0.2323

Colors that go with #537ef3

Charcoal, Red 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 →

#f3c853

#53cef3 · #7953f3

#f3537e · #7ef353

Split-complementary

Open in tool →

#f37953 · #cef353

#f353ce · #f3c853 · #53f379

Contrast

#537ef3 as textRatioAAAA largeAAAFix
Aaon white
3.72:1failpassfail
  • AA: use #3b6cf1 as the text (4.56:1)
  • AAA: use #1047e0 as the text (7:1)
  • AA: or shift the background to #1c1c1c (4.58:1)
Aaon black
5.65:1passpassfail
  • AAA: use #7093f5 as the text (7.18:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #537ef3 as the background.

Brands using this color

Fonts for this mood

#537ef3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #537ef3
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 #537ef3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/537ef3-9ca2c4-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