# #031b59

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

## Values

- Hex: `#031b59`
- RGB: rgb(3, 27, 89)
- HSL: hsl(223, 93%, 18%)
- OKLCH: oklch(0.255 0.115 263.2)
- Relative luminance: 0.0152
- Nearest named color: Dark Soul (#112255, Δ 2.714) — https://brandsweets.com/colors/dark-soul
- Moods: cool, vivid, dark, technical, modern, luxury, bold
- Page: https://brandsweets.com/colors/031b59

## Tints & shades

- Tints (toward white): #052880, #0634a7, #0740cf, #094cf6, #3069f8, #5885f9, #7fa2fa, #a6bffc, #cedbfd, #f5f8ff
- Shades (toward black): #031a54, #03174a, #021545, #02123b, #021136, #020f31, #010c27, #010b22, #010819, #010614

## Harmonies

- Complementary: #594003
- Analogous: #034659, #160359
- Triadic: #59031b, #1b5903
- Split-complementary: #591603, #465903
- Tetradic: #590346, #594003, #035916

## Colors that go with #031b59

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 #031b59: softer than #000 and cool enough to feel like part of the same palette. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), CeraVe (https://brandsweets.com/colors/brands/cerave-com), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Volkswagen (https://brandsweets.com/colors/brands/vw-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #031b59 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/crimson
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #031b59's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Deep Water (https://brandsweets.com/palettes/dark#deep-water), Glacier (https://brandsweets.com/palettes/cool#glacier), Plaid (https://brandsweets.com/colors/brands/plaid-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #031b59 in 6 real palettes, including Southwest Airlines's brand system and Beach Hut, as the accent. Seen in: Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 11 real palettes, including Monzo's brand system and Penpot's brand system put Blue beside #031b59, as the accent. Seen in: Monzo (https://brandsweets.com/colors/brands/monzo-com), Penpot (https://brandsweets.com/colors/brands/penpot-app), Sketch (https://brandsweets.com/colors/brands/sketch-com), League of Legends (https://brandsweets.com/colors/brands/leagueoflegends-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #031b59: 7 real palettes, including SoFi's brand system and Open House, as the supporting colour. Seen in: SoFi (https://brandsweets.com/colors/brands/sofi-com), Open House (https://brandsweets.com/palettes/clean#open-house), Coastal (https://brandsweets.com/palettes/cool#coastal), Arctic (https://brandsweets.com/palettes/clean#arctic). — https://brandsweets.com/colors/cadetblue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #031b59: 10 real palettes, including Blue Mono and Glacier, as the lead colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Glacier (https://brandsweets.com/palettes/cool#glacier), MLB (https://brandsweets.com/colors/brands/mlb-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/cobalt
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #031b59: 4 real palettes, including Blue Mono and Arctic, as the supporting colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Arctic (https://brandsweets.com/palettes/clean#arctic), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Retool (https://brandsweets.com/colors/brands/retool-com). — https://brandsweets.com/colors/cornflowerblue

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

- On white (#ffffff): 16.09:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.3:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #3069f8 (4.5:1); AA: background → #8a8a8a (4.66:1); AAA: text → #6b94fa (7.24:1); AAA: background → #ababab (7.01:1)

## Brands using this color

- **Airbus** — secondary #00205b (Δ 1.341) — https://brandsweets.com/colors/brands/airbus-com
- **Gillette** — secondary #001e60 (Δ 1.496) — https://brandsweets.com/colors/brands/gillette-com

## 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/031b59-9ca3c4-df704e-211f2d-e9eff1?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: "#031b59" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.