# #3f5183

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

## Values

- Hex: `#3f5183`
- RGB: rgb(63, 81, 131)
- HSL: hsl(224, 35%, 38%)
- OKLCH: oklch(0.444 0.086 267.8)
- Relative luminance: 0.0858
- Nearest named color: Assassin (#2d4f83, Δ 2.329) — https://brandsweets.com/colors/assassin
- Moods: cool, modern
- Page: https://brandsweets.com/colors/3f5183

## Tints & shades

- Tints (toward white): #495e97, #536bac, #687cb6, #7c8ec0, #91a0ca, #a5b2d4, #bac4de, #cfd5e8, #e3e7f2, #f8f9fc
- Shades (toward black): #3a4b78, #33426b, #2e3c60, #283353, #232d48, #1e263e, #171e30, #121726, #0c0f18, #07090e

## Harmonies

- Complementary: #83713f
- Analogous: #3f7383, #4f3f83
- Triadic: #833f51, #51833f
- Split-complementary: #834f3f, #73833f
- Tetradic: #833f73, #83713f, #3f834f

## Colors that go with #3f5183

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

- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #3f5183 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Subaru (https://brandsweets.com/colors/brands/subaru-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3f5183'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), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 7 real palettes, including Tesco's brand system and CVS's brand system put Blue beside #3f5183, as the supporting colour. Seen in: Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Activision (https://brandsweets.com/colors/brands/activision-com). — https://brandsweets.com/colors/blue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #3f5183: 4 real palettes, including Coca-Cola's brand system and Blue Mono, as the supporting colour. Seen in: Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Gopro (https://brandsweets.com/colors/brands/gopro-com), Blizzard (https://brandsweets.com/colors/brands/blizzard-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f5183 in 14 real palettes, including Walgreens's brand system and Wells Fargo's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/crimson
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #3f5183: 5 real palettes, including Campbell's's brand system and Fireside, as the supporting colour. Seen in: Campbell's (https://brandsweets.com/colors/brands/campbells-com), Fireside (https://brandsweets.com/palettes/dark#fireside), AT&T (https://brandsweets.com/colors/brands/att-com), Wendy's (https://brandsweets.com/colors/brands/wendys-com). — https://brandsweets.com/colors/firebrick
- **Goldenrod** #daa520 [pool] — Goldenrod shows up next to #3f5183 in 5 real palettes, including Open House and Sapphire & Gold, as the accent. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Mid-Century (https://brandsweets.com/palettes/warm#mid-century), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/goldenrod
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3f5183: 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): 7.73:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.72:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5d74b1 (4.6:1); AA: background → #c7c7c7 (4.57:1); AAA: text → #8797c5 (7.26:1); AAA: background → #f5f5f5 (7.09:1)

## Fonts for this mood

- 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/3f5183-9ca2c4-df724e-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: "#3f5183" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.