Color

#133f81

#133f81
hex#133f81
rgbrgb(19, 63, 129)
hslhsl(216, 74%, 29%)
oklchoklch(0.379 0.121 258.9)
Closest name: Aegean Blue (#1b416f)Relative luminance 0.0528

Colors that go with #133f81

Crimson, Steel Blue and 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 →

#815513

#137681 · #1e1381

#81133f · #3f8113

Split-complementary

Open in tool →

#811e13 · #768113

#811376 · #815513 · #13811e

Contrast

#133f81 as textRatioAAAA largeAAAFix
Aaon white
10.22:1passpasspassPasses AAA — no fix needed.
Aaon black
2.06:1failfailfail
  • AA: use #2a72df as the text (4.57:1)
  • AAA: use #5f96e7 as the text (7:1)
  • AA: or shift the background to #adadad (4.55:1)
  • AAA: or shift the background to #d6d6d6 (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #133f81 as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Palettes built around it

Fonts for this mood

#133f81 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #133f81
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 #133f81 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/133f81-9ca7c4-df5f4e-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