# #303d64

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

## Values

- Hex: `#303d64`
- RGB: rgb(48, 61, 100)
- HSL: hsl(225, 35%, 29%)
- OKLCH: oklch(0.368 0.07 268.9)
- Relative luminance: 0.0489
- Nearest named color: Black Turmeric (#2c4364, Δ 1.879) — https://brandsweets.com/colors/black-turmeric
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/303d64

## Tints & shades

- Tints (toward white): #3c4c7c, #475a94, #5369ac, #6b7eb8, #8393c3, #98a5cd, #b0bad9, #c8cfe4, #e0e4f0, #f8f9fc
- Shades (toward black): #2d395d, #283253, #242e4c, #1f2841, #1c243b, #171d30, #141929, #0f131f, #0c0f18, #07080e

## Harmonies

- Complementary: #645730
- Analogous: #305764, #3d3064
- Triadic: #64303d, #3d6430
- Split-complementary: #643d30, #576430
- Tetradic: #643057, #645730, #30643d

## Colors that go with #303d64

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 #303d64'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), Plaid (https://brandsweets.com/colors/brands/plaid-com), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/steelblue
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #303d64 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Olive Grove (https://brandsweets.com/palettes/muted#olive-grove). — https://brandsweets.com/colors/darkolivegreen
- **Blue** #0000ff [pool] — 12 real palettes, including Alaska Airlines's brand system and Jeep's brand system put Blue beside #303d64, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Jeep (https://brandsweets.com/colors/brands/jeep-com), Minecraft (https://brandsweets.com/colors/brands/minecraft-net), Dunkin' (https://brandsweets.com/colors/brands/dunkindonuts-com). — https://brandsweets.com/colors/blue
- **Blush Pink** #e8b4b8 [pool] — 4 real palettes, including Nursery and Garden Wedding put Blush Pink beside #303d64, as the lead colour. Seen in: Nursery (https://brandsweets.com/palettes/light#nursery), Garden Wedding (https://brandsweets.com/palettes/light#garden-wedding), Rain Garden (https://brandsweets.com/palettes/cool#rain-garden), Blush (https://brandsweets.com/palettes/light#blush). — https://brandsweets.com/colors/blush-pink
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #303d64: 5 real palettes, including Open House and Coastal, as the supporting colour. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Coastal (https://brandsweets.com/palettes/cool#coastal), Clean Beauty (https://brandsweets.com/palettes/minimal#clean-beauty), Paper & Pine (https://brandsweets.com/palettes/minimal#paper-and-pine). — https://brandsweets.com/colors/cadetblue
- **Copper** #b87333 [pool] — Designers have shipped Copper with #303d64: 4 real palettes, including Notion's brand system and Clean Beauty. Seen in: Notion (https://brandsweets.com/colors/brands/notion), Clean Beauty (https://brandsweets.com/palettes/minimal#clean-beauty), Dusk (https://brandsweets.com/palettes/cool#dusk), Desert Road (https://brandsweets.com/palettes/warm#desert-road). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #303d64 in 10 real palettes, including Marvel's brand system and Frost & Ember, as the accent. Seen in: Marvel (https://brandsweets.com/colors/brands/marvel-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com). — https://brandsweets.com/colors/crimson
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #303d64: 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): 10.62:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.98:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5d72b1 (4.51:1); AA: background → #ababab (4.63:1); AAA: text → #8796c5 (7.2:1); AAA: background → #d4d4d4 (7.17:1)

## Brands using this color

- **Harley-Davidson** — accent #383b5e (Δ 1.511) — https://brandsweets.com/colors/brands/harley-davidson-com

## 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/303d64-9ca1c4-df754e-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: "#303d64" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.