Color

#21305f

#21305f
hex#21305f
rgbrgb(33, 48, 95)
hslhsl(225, 48%, 25%)
oklchoklch(0.323 0.086 268.1)
Closest name: Deep Sea Base (#2c2c57)Relative luminance 0.0326

Colors that go with #21305f

Dark Olive Green, Sea Green and Steel 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 →

#5e4f21

#214f5e · #30215e

#5e2130 · #305e21

Split-complementary

Open in tool →

#5e3021 · #4f5e21

#5e214f · #5e4f21 · #215e30

Contrast

#21305f as textRatioAAAA largeAAAFix
Aaon white
12.71:1passpasspassPasses AAA — no fix needed.
Aaon black
1.65:1failfailfail
  • AA: use #5571c3 as the text (4.54:1)
  • AAA: use #7f93d2 as the text (7.01:1)
  • AA: or shift the background to #9c9c9c (4.63:1)
  • AAA: or shift the background to #c2c2c2 (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #21305f as the background.

Brands using this color

Fonts for this mood

#21305f reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #21305f
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 #21305f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/21305f-9ca1c4-df754e-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