# #3f4a73

A color — cool, muted. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#3f4a73`
- RGB: rgb(63, 74, 115)
- HSL: hsl(227, 29%, 35%)
- OKLCH: oklch(0.419 0.07 271.7)
- Relative luminance: 0.0719
- Nearest named color: Bonne Nuit (#3a4866, Δ 2.355) — https://brandsweets.com/colors/bonne-nuit
- Moods: cool, muted
- Page: https://brandsweets.com/colors/3f4a73

## Tints & shades

- Tints (toward white): #4a5787, #57669e, #6876ac, #7b88b7, #929dc3, #a6afce, #bac1d9, #ced2e4, #e5e7f1, #f8f9fb
- Shades (toward black): #3a4469, #353e5f, #2f3756, #2a314c, #242b42, #1d2235, #181c2b, #121521, #0d0f17, #07090d

## Harmonies

- Complementary: #73683f
- Analogous: #3f6473, #4e3f73
- Triadic: #733f4b, #4b733f
- Split-complementary: #734e3f, #64733f
- Tetradic: #733f64, #73683f, #3f734e

## Colors that go with #3f4a73

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 #3f4a73's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Auth0 (https://brandsweets.com/colors/brands/auth0-com), Capital One (https://brandsweets.com/colors/brands/capitalone-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 7 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #3f4a73, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Jeep (https://brandsweets.com/colors/brands/jeep-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #3f4a73: 4 real palettes, including Dusk and Open House, as the supporting colour. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Open House (https://brandsweets.com/palettes/clean#open-house), Alpine (https://brandsweets.com/palettes/cool#alpine), Paper & Pine (https://brandsweets.com/palettes/minimal#paper-and-pine). — https://brandsweets.com/colors/cadetblue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f4a73 in 10 real palettes, including Codecademy's brand system and Walgreens's brand system, as the accent. Seen in: Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #3f4a73: 14 real palettes, including HP's brand system and Hinge's brand system, as the accent. Seen in: HP (https://brandsweets.com/colors/brands/hp-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Starlink (https://brandsweets.com/colors/brands/starlink-com). — https://brandsweets.com/colors/denim
- **Goldenrod** #daa520 [pool] — Goldenrod shows up next to #3f4a73 in 5 real palettes, including Sapphire & Gold and Disney's brand system, as the supporting colour. Seen in: Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Disney (https://brandsweets.com/colors/brands/disney-com), Open House (https://brandsweets.com/palettes/clean#open-house), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/goldenrod
- **Midnight Blue** #191970 [pool] — 13 real palettes, including First Snow and Microsoft's brand system put Midnight Blue beside #3f4a73, as that palette's text colour. Seen in: First Snow (https://brandsweets.com/palettes/cool#first-snow), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Lufthansa (https://brandsweets.com/colors/brands/lufthansa-com), FIFA (https://brandsweets.com/colors/brands/fifa-com). — https://brandsweets.com/colors/midnightblue
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3f4a73: 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): 8.61:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.44:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6473aa (4.57:1); AA: background → #bdbdbd (4.58:1); AAA: text → #8994be (7.04:1); AAA: background → #e8e8e8 (7.03:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3f4a73-9ca0c4-df7a4e-221f2d-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: "#3f4a73" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.