# #663b72

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

## Values

- Hex: `#663b72`
- RGB: rgb(102, 59, 114)
- HSL: hsl(287, 32%, 34%)
- OKLCH: oklch(0.427 0.101 318.6)
- Relative luminance: 0.0717
- Nearest named color: Heartless (#623b70, Δ 0.836) — https://brandsweets.com/colors/heartless
- Moods: cool, muted
- Page: https://brandsweets.com/colors/663b72

## Tints & shades

- Tints (toward white): #784587, #8e519e, #9d61ae, #ab78ba, #b88dc4, #c5a1ce, #d3b8db, #e0cde5, #eee4f1, #fbf8fc
- Shades (toward black): #5d3668, #54315e, #4b2b54, #42264a, #392140, #301c36, #27172c, #1e1122, #150c18, #0c070d

## Harmonies

- Complementary: #47723b
- Analogous: #4b3b72, #723b63
- Triadic: #72663b, #3b7266
- Split-complementary: #63723b, #3b724b
- Tetradic: #724b3b, #47723b, #3b6372

## Colors that go with #663b72

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 #663b72: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Harbour (https://brandsweets.com/palettes/cool#harbour), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: complementary] — Sea Green sits directly opposite #663b72 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Subaru (https://brandsweets.com/colors/brands/subaru-com). — https://brandsweets.com/colors/seagreen
- **Crimson** #dc143c [pool] — Crimson is paired with #663b72 in 4 real palettes, including Wells Fargo's brand system and Lenovo's brand system, as the lead colour. Seen in: Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Lenovo (https://brandsweets.com/colors/brands/lenovo-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #663b72: 5 real palettes, including Hinge's brand system and HP's brand system, as the accent. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), HP (https://brandsweets.com/colors/brands/hp-com), Slack (https://brandsweets.com/colors/brands/slack-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/denim
- **Powder Blue** #b0e0e6 [pool] — Designers have shipped Powder Blue with #663b72: 4 real palettes, including First Snow and Nursery, as the accent. Seen in: First Snow (https://brandsweets.com/palettes/cool#first-snow), Nursery (https://brandsweets.com/palettes/light#nursery), Macaron (https://brandsweets.com/palettes/light#macaron), Stone (https://brandsweets.com/palettes/neutral#stone). — https://brandsweets.com/colors/powderblue
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #663b72 in 6 real palettes, including Console Light and Wayfair's brand system, as the lead colour. Seen in: Console Light (https://brandsweets.com/palettes/technical#console-light), Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Stripe (https://brandsweets.com/colors/brands/stripe), GitHub (https://brandsweets.com/colors/brands/github). — https://brandsweets.com/colors/royalblue
- **Taupe** #483c32 [pool] — Taupe is paired with #663b72 in 8 real palettes, including Datadog's brand system and Blush, as that palette's text colour. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), Blush (https://brandsweets.com/palettes/light#blush), Dusk (https://brandsweets.com/palettes/cool#dusk), GitHub (https://brandsweets.com/colors/brands/github). — https://brandsweets.com/colors/taupe
- **Teal** #008080 [harmony, pool: split] — Teal is a split-complement of #663b72: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Stanley (https://brandsweets.com/colors/brands/stanley1913-com). — https://brandsweets.com/colors/teal

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

- On white (#ffffff): 8.63:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.43:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9b5dac (4.56:1); AA: background → #bdbdbd (4.59:1); AAA: text → #b486c1 (7.12:1); AAA: background → #e8e8e8 (7.04:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/663b72-bd9fc1-abcb62-2d1f2a-ece9f1?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: "#663b72" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.