Color

#3f28eb

#3f28eb
hex#3f28eb
rgbrgb(63, 40, 235)
hslhsl(247, 83%, 54%)
oklchoklch(0.47 0.266 274.3)
Closest name: Blustering Blue (#4411ff)Relative luminance 0.0857

Colors that go with #3f28eb

Charcoal, Cobalt Blue and Cornflower Blue 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 →

#d4eb28

#2873eb · #a028eb

#eb3f28 · #28eb3f

Split-complementary

Open in tool →

#eba028 · #73eb28

#eb2873 · #d4eb28 · #28eba0

Contrast

#3f28eb as textRatioAAAA largeAAAFix
Aaon white
7.74:1passpasspassPasses AAA — no fix needed.
Aaon black
2.71:1failfailfail
  • AA: use #7160f0 as the text (4.63:1)
  • AAA: use #978af4 as the text (7.26:1)
  • AA: or shift the background to #c7c7c7 (4.58:1)
  • AAA: or shift the background to #f5f5f5 (7.1:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3f28eb as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#3f28eb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3f28eb
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 #3f28eb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3f28eb-a59cc4-dfaa4e-271f2d-e9ecf1?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