Color

#100f57

#100f57
hex#100f57
rgbrgb(16, 15, 87)
hslhsl(241, 71%, 20%)
oklchoklch(0.237 0.123 272.4)
Closest name: Interstellar Blue (#001155)Relative luminance 0.0114

Colors that go with #100f57

Charcoal, 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 →

#56570f

#0f3257 · #340f57

#57100f · #0f5710

Split-complementary

Open in tool →

#57340f · #32570f

#570f32 · #56570f · #0f5734

Contrast

#100f57 as textRatioAAAA largeAAAFix
Aaon white
17.1:1passpasspassPasses AAA — no fix needed.
Aaon black
1.23:1failfailfail
  • AA: use #6866e5 as the text (4.62:1)
  • AAA: use #8f8eec as the text (7.25:1)
  • AA: or shift the background to #858585 (4.63:1)
  • AAA: or shift the background to #a6a6a6 (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 #100f57 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

#100f57 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #100f57
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 #100f57 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/100f57-a19cc4-df9b4e-261f2d-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