# #183d81

A color — cool, vivid, dark, technical, modern, luxury, bold. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#183d81`
- RGB: rgb(24, 61, 129)
- HSL: hsl(219, 69%, 30%)
- OKLCH: oklch(0.376 0.123 261.3)
- Relative luminance: 0.0512
- Nearest named color: Deep Space Royal (#223382, Δ 2.682) — https://brandsweets.com/colors/deep-space-royal
- Moods: cool, vivid, dark, technical, modern, luxury, bold
- Page: https://brandsweets.com/colors/183d81

## Tints & shades

- Tints (toward white): #1d4b9f, #2359be, #2865d7, #467bdd, #6490e3, #82a6e8, #a0bbee, #bacef2, #d8e3f8, #f6f9fd
- Shades (toward black): #153774, #14336c, #112c5f, #102856, #0d2249, #0b1c3c, #091834, #071227, #060e1e, #030811

## Harmonies

- Complementary: #815c18
- Analogous: #187181, #281881
- Triadic: #81183d, #3d8118
- Split-complementary: #812818, #718118
- Tetradic: #811871, #815c18, #188128

## Colors that go with #183d81

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #183d81's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 5 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #183d81, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Tesco (https://brandsweets.com/colors/brands/tesco-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #183d81 in 9 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour. Seen in: Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #183d81: 17 real palettes, including Hasbro's brand system and Unilever's brand system, as the supporting colour. Seen in: Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Unilever (https://brandsweets.com/colors/brands/unilever-com), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com). — https://brandsweets.com/colors/denim
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #183d81 in 5 real palettes, including NASA's brand system and Tide's brand system, as the supporting colour. Seen in: NASA (https://brandsweets.com/colors/brands/nasa-gov), Tide (https://brandsweets.com/colors/brands/tide-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), HubSpot (https://brandsweets.com/colors/brands/hubspot-com). — https://brandsweets.com/colors/orangered
- **Powder Blue** #b0e0e6 [pool] — Designers have shipped Powder Blue with #183d81: 4 real palettes, including Glacier and First Snow, as the supporting colour. Seen in: Glacier (https://brandsweets.com/palettes/cool#glacier), First Snow (https://brandsweets.com/palettes/cool#first-snow), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Macaron (https://brandsweets.com/palettes/light#macaron). — https://brandsweets.com/colors/powderblue
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #183d81 in 11 real palettes, including Nokia's brand system and Confluent's brand system, as the supporting colour. Seen in: Nokia (https://brandsweets.com/colors/brands/nokia-com), Confluent (https://brandsweets.com/colors/brands/confluent-io), Nivea (https://brandsweets.com/colors/brands/nivea-com), Carrefour (https://brandsweets.com/colors/brands/carrefour-com). — https://brandsweets.com/colors/royalblue
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #183d81: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy. — https://brandsweets.com/colors/whitesmoke

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 10.38:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.02:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #3971db (4.56:1); AA: background → #ababab (4.52:1); AAA: text → #6c96e4 (7.12:1); AAA: background → #d4d4d4 (7:1)

## Curated palettes containing it

- **Glacier** (winter, cool, clean, technical) — #0077b6, #90e0ef, #023e8a, #f3f9fc, #03045e — Three blues from ice to deep water on a pale surface — a monochromatic winter set with real depth. — tool: https://brandsweets.com/palettes/new/0077b6-90e0ef-023e8a-f3f9fc-03045e — collection: https://brandsweets.com/palettes/winter
- **Sapphire & Gold** (jewel-tones, luxury, cool, elegant) — #1e3a8a, #c9a227, #0e7490, #f7f6f2, #111827 — Deep sapphire and gold with a teal — old-money jewel tones on an ivory ground; heraldic without a crest. — tool: https://brandsweets.com/palettes/new/1e3a8a-c9a227-0e7490-f7f6f2-111827 — collection: https://brandsweets.com/palettes/jewel-tones

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- modern: https://brandsweets.com/fonts/mood/modern
- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/183d81-9ca5c4-df664e-211f2d-e9f0f1?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#183d81" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.