Color

#3988ea

#3988ea
hex#3988ea
rgbrgb(57, 136, 234)
hslhsl(213, 81%, 57%)
oklchoklch(0.627 0.167 255.6)
Closest name: Blue Jay (#5588dd)Relative luminance 0.2442

Colors that go with #3988ea

Charcoal, Crimson and Copper 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 →

#ea9a39

#39e1ea · #4139ea

#ea3988 · #88ea39

Split-complementary

Open in tool →

#ea4139 · #e1ea39

#ea39e1 · #ea9a39 · #39ea41

Contrast

#3988ea as textRatioAAAA largeAAAFix
Aaon white
3.57:1failpassfail
  • AA: use #1873e2 as the text (4.58:1)
  • AAA: use #1257ab as the text (7.05:1)
  • AA: or shift the background to #212121 (4.51:1)
Aaon black
5.88:1passpassfail
  • AAA: use #5499ed as the text (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 #3988ea as the background.

Brands using this color

Fonts for this mood

#3988ea reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3988ea
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 #3988ea and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3988ea-9ca9c4-df584e-1f202d-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