Color

#3700db

#3700db
hex#3700db
rgbrgb(55, 0, 219)
hslhsl(255, 100%, 43%)
oklchoklch(0.423 0.268 274.3)
Closest name: Busty Blue (#3300cc)Relative luminance 0.0593

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a4db00

#0037db · #a400db

#db3700 · #00db37

Split-complementary

Open in tool →

#dba400 · #37db00

#db0037 · #a4db00 · #00dba4

Contrast

#3700db as textRatioAAAA largeAAAFix
Aaon white
9.61:1passpasspassPasses AAA — no fix needed.
Aaon black
2.19:1failfailfail
  • AA: use #7d52ff as the text (4.52:1)
  • AAA: use #9f80ff as the text (7.01:1)
  • AA: or shift the background to #b3b3b3 (4.58:1)
  • AAA: or shift the background to #dedede (7.14:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3700db 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

#3700db reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3700db
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 #3700db and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3700db-ab9cc4-dfbd4e-291f2d-e9ebf1?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