# #183f8b

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

## Values

- Hex: `#183f8b`
- RGB: rgb(24, 63, 139)
- HSL: hsl(220, 71%, 32%)
- OKLCH: oklch(0.388 0.134 261.9)
- Relative luminance: 0.0561
- Nearest named color: Cascade Twilight (#234893, Δ 3.075) — https://brandsweets.com/colors/cascade-twilight
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/183f8b

## Tints & shades

- Tints (toward white): #1d4caa, #2158c4, #2e68dc, #487be0, #6691e5, #85a7ea, #9fbaef, #bed0f4, #d8e3f8, #f6f9fe
- Shades (toward black): #15387e, #133371, #122f69, #10295c, #0d234e, #0b1d41, #091734, #07132c, #050e1f, #030811

## Harmonies

- Complementary: #8c6518
- Analogous: #18788c, #2b188c
- Triadic: #8c183e, #3e8c18
- Split-complementary: #8c2b18, #788c18
- Tetradic: #8c1878, #8c6518, #188c2b

## Colors that go with #183f8b

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

- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #183f8b: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Harbour (https://brandsweets.com/palettes/cool#harbour), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/charcoal
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #183f8b'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 CVS's brand system and Procter & Gamble's brand system put Blue beside #183f8b, as the supporting colour. Seen in: CVS (https://brandsweets.com/colors/brands/cvs-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Tesco (https://brandsweets.com/colors/brands/tesco-com). — https://brandsweets.com/colors/blue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #183f8b: 4 real palettes, including Blue Mono and Gopro's brand system, as the supporting colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Gopro (https://brandsweets.com/colors/brands/gopro-com), Peacock (https://brandsweets.com/colors/brands/peacocktv-com), Blizzard (https://brandsweets.com/colors/brands/blizzard-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #183f8b in 12 real palettes, including Walgreens's brand system and Casper Sleep's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #183f8b: 15 real palettes, including Unilever's brand system and Warbyparker's brand system, as the accent. Seen in: Unilever (https://brandsweets.com/colors/brands/unilever-com), Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Hasbro (https://brandsweets.com/colors/brands/hasbro-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/denim
- **Midnight Blue** #191970 [pool] — 17 real palettes, including Fintech Trust and First Snow put Midnight Blue beside #183f8b, as that palette's text colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), First Snow (https://brandsweets.com/palettes/cool#first-snow), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono). — https://brandsweets.com/colors/midnightblue
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #183f8b in 4 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), Soundcloud (https://brandsweets.com/colors/brands/soundcloud-com). — https://brandsweets.com/colors/orangered

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

- On white (#ffffff): 9.89:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.12:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #3b71de (4.6:1); AA: background → #b0b0b0 (4.56:1); AAA: text → #6b94e6 (7:1); AAA: background → #d9d9d9 (7.01:1)

## Brands using this color

- **Nokia** — primary #124191 (Δ 1.107) — https://brandsweets.com/colors/brands/nokia-com
- **NASA** — primary #0b3d91 (Δ 1.433) — https://brandsweets.com/colors/brands/nasa-gov

## Curated palettes containing it

- **Fintech Trust** (cool, clean, modern) — #0b3d91, #4b6a9b, #00a878, #ffffff, #0b1f3a — Navy signals custody and stability; the green accent is money moving the right way. No red anywhere except errors. — tool: https://brandsweets.com/palettes/new/0b3d91-4b6a9b-00a878-ffffff-0b1f3a — collection: https://brandsweets.com/palettes/cool
- **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

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/183f8b-9ca5c4-df694e-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: "#183f8b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.