Color

#3939ef

#3939ef
hex#3939ef
rgbrgb(57, 57, 239)
hslhsl(240, 85%, 58%)
oklchoklch(0.49 0.259 271.5)
Closest name: Blustering Blue (#4411ff)Relative luminance 0.1003

Tints & shades

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

Harmonies

Complementary

Open in tool →

#efef39

#3994ef · #9439ef

#ef3939 · #39ef39

Split-complementary

Open in tool →

#ef9439 · #94ef39

#ef3994 · #efef39 · #39ef94

Contrast

#3939ef as textRatioAAAA largeAAAFix
Aaon white
6.99:1passpassfail
  • AAA: use #3434ef as the text (7.28:1)
Aaon black
3.01:1failpassfail
  • AA: use #6363f2 as the text (4.6:1)
  • AAA: use #8e8ef6 as the text (7.35:1)
  • AA: or shift the background to #d1d1d1 (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3939ef 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

#3939ef reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3939ef
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 #3939ef and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3939ef-a19cc4-df994e-251f2d-e9edf1?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