Color

#3975d5

#3975d5
hex#3975d5
rgbrgb(57, 117, 213)
hslhsl(217, 65%, 53%)
oklchoklch(0.573 0.16 259.5)
Closest name: Royal Blue (#4169e1)Relative luminance 0.184

Colors that go with #3975d5

Charcoal, Sea Green 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 →

#d59939

#39c3d5 · #4b39d5

#d53975 · #75d539

Split-complementary

Open in tool →

#d54b39 · #c3d539

#d539c3 · #d59939 · #39d54b

Contrast

#3975d5 as textRatioAAAA largeAAAFix
Aaon white
4.49:1failpassfail
  • AA: use #3572d4 as the text (4.66:1)
  • AAA: use #2354a4 as the text (7.3:1)
  • AA: or shift the background to #050505 (4.54:1)
Aaon black
4.68:1passpassfail
  • AAA: use #6c98e0 as the text (7.21:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3975d5 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

#3975d5 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3975d5
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 #3975d5 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3975d5-9ca7c4-df624e-201f2d-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