# #3f4e73

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

## Values

- Hex: `#3f4e73`
- RGB: rgb(63, 78, 115)
- HSL: hsl(223, 29%, 35%)
- OKLCH: oklch(0.428 0.065 266.8)
- Relative luminance: 0.0774
- Nearest named color: Bonne Nuit (#3a4866, Δ 2.718) — https://brandsweets.com/colors/bonne-nuit
- Moods: cool, muted
- Page: https://brandsweets.com/colors/3f4e73

## Tints & shades

- Tints (toward white): #4a5b87, #576b9e, #687bac, #7b8cb7, #92a0c3, #a6b1ce, #bac3d9, #ced4e4, #e5e8f1, #f8f9fb
- Shades (toward black): #3a4769, #35415f, #2f3a56, #2a334c, #242d42, #1d2435, #181d2b, #121621, #0d1017, #07090d

## Harmonies

- Complementary: #73643f
- Analogous: #3f6873, #4b3f73
- Triadic: #733f4e, #4e733f
- Split-complementary: #734b3f, #68733f
- Tetradic: #733f68, #73643f, #3f734b

## Colors that go with #3f4e73

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 #3f4e73's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Capital One (https://brandsweets.com/colors/brands/capitalone-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 6 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #3f4e73, 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 #3f4e73: 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 #3f4e73 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), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #3f4e73: 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 #3f4e73 in 5 real palettes, including Open House and Disney's brand system, as the accent. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Disney (https://brandsweets.com/colors/brands/disney-com), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/goldenrod
- **Medium Sea Green** #3cb371 [pool] — Medium Sea Green is paired with #3f4e73 in 4 real palettes, including Console Light and Mint Modern, as the accent. Seen in: Console Light (https://brandsweets.com/palettes/technical#console-light), Mint Modern (https://brandsweets.com/palettes/modern#mint-modern), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Undergrowth (https://brandsweets.com/palettes/dark#undergrowth). — https://brandsweets.com/colors/mediumseagreen
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3f4e73: 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): 8.24:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.55:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6175a8 (4.62:1); AA: background → #c2c2c2 (4.63:1); AAA: text → #8595bc (7.02:1); AAA: background → #ededed (7.04:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3f4e73-9ca3c4-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: "#3f4e73" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.