# #181b59

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

## Values

- Hex: `#181b59`
- RGB: rgb(24, 27, 89)
- HSL: hsl(237, 58%, 22%)
- OKLCH: oklch(0.266 0.109 274.1)
- Relative luminance: 0.017
- Nearest named color: Dark Soul (#112255, Δ 2.079) — https://brandsweets.com/colors/dark-soul
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/181b59

## Tints & shades

- Tints (toward white): #202579, #282d95, #3037b5, #3e45cc, #5e64d4, #7e83dd, #9a9ee4, #bbbded, #d7d8f4, #f7f7fd
- Shades (toward black): #151851, #131649, #121544, #10123c, #0e1034, #0c0d2c, #0a0b24, #090a20, #060718, #040510

## Harmonies

- Complementary: #595518
- Analogous: #183b59, #351859
- Triadic: #59181b, #1b5918
- Split-complementary: #593518, #3b5918
- Tetradic: #59183b, #595518, #185935

## Colors that go with #181b59

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 #181b59: 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
- **Dark Olive Green** #556b2f [harmony, pool: split] — Dark Olive Green is a split-complement of #181b59: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Cohere (https://brandsweets.com/colors/brands/cohere-com), 7-Eleven (https://brandsweets.com/colors/brands/7-eleven-com), Warp (https://brandsweets.com/colors/brands/warp-dev), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal). — https://brandsweets.com/colors/darkolivegreen
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #181b59 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Subaru (https://brandsweets.com/colors/brands/subaru-com), Asana (https://brandsweets.com/colors/brands/asana-com), Intel (https://brandsweets.com/colors/brands/intel-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #181b59's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Glacier (https://brandsweets.com/palettes/cool#glacier), Discover (https://brandsweets.com/colors/brands/discover-com). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #181b59 in 7 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] — 14 real palettes, including Monzo's brand system and Sketch's brand system put Blue beside #181b59, as the accent. Seen in: Monzo (https://brandsweets.com/colors/brands/monzo-com), Sketch (https://brandsweets.com/colors/brands/sketch-com), Penpot (https://brandsweets.com/colors/brands/penpot-app), 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 #181b59: 8 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 #181b59: 12 real palettes, including Blue Mono and MLB's brand system, as the lead colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), MLB (https://brandsweets.com/colors/brands/mlb-com), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/cobalt

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

- On white (#ffffff): 15.67:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.34:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #666cd6 (4.68:1); AA: background → #8a8a8a (4.54:1); AAA: text → #8a8ee0 (7.03:1); AAA: background → #b0b0b0 (7.23:1)

## Fonts for this mood

- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold
- 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/181b59-9f9cc4-df924e-251f2d-e9edf1?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: "#181b59" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.