Color

#313d5e

#313d5e
hex#313d5e
rgbrgb(49, 61, 94)
hslhsl(224, 31%, 28%)
oklchoklch(0.365 0.059 268.2)
Closest name: Black Turmeric (#2c4364)Relative luminance 0.048

Colors that go with #313d5e

Sea Green, Steel Blue and Dark Olive Green 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 →

#5e5231

#31535e · #3c315e

#5e313d · #3d5e31

Split-complementary

Open in tool →

#5e3c31 · #535e31

#5e3153 · #5e5231 · #315e3c

Contrast

#313d5e as textRatioAAAA largeAAAFix
Aaon white
10.72:1passpasspassPasses AAA — no fix needed.
Aaon black
1.96:1failfailfail
  • AA: use #5f73ab as the text (4.53:1)
  • AAA: use #8796c0 as the text (7.15:1)
  • AA: or shift the background to #a8a8a8 (4.51:1)
  • AAA: or shift the background to #d1d1d1 (7.02:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #313d5e as the background.

Brands using this color

Fonts for this mood

#313d5e reads as cool, muted, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #313d5e
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 #313d5e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/313d5e-9ca2c4-df724e-221f2d-e9eff1?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