# #663a73

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

## Values

- Hex: `#663a73`
- RGB: rgb(102, 58, 115)
- HSL: hsl(286, 33%, 34%)
- OKLCH: oklch(0.426 0.104 318.2)
- Relative luminance: 0.0709
- Nearest named color: Heartless (#623b70, Δ 0.95) — https://brandsweets.com/colors/heartless
- Moods: cool, muted
- Page: https://brandsweets.com/colors/663a73

## Tints & shades

- Tints (toward white): #784488, #8d509f, #9c60af, #ab77bb, #b88cc5, #c4a0cf, #d3b8db, #dfcce5, #eee4f1, #fbf8fc
- Shades (toward black): #5d3569, #54305f, #4b2b55, #42264b, #392040, #301b36, #27162c, #1e1122, #150c18, #0c070e

## Harmonies

- Complementary: #47733a
- Analogous: #493a73, #733a64
- Triadic: #73663a, #3a7366
- Split-complementary: #64733a, #3a7349
- Tetradic: #73493a, #47733a, #3a6473

## Colors that go with #663a73

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 #663a73: 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 #663a73 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). — https://brandsweets.com/colors/seagreen
- **Crimson** #dc143c [pool] — Crimson is paired with #663a73 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), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #663a73: 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 #663a73: 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 #663a73 in 5 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 #663a73 in 6 real palettes, including Datadog's brand system and Dusk, as that palette's text colour. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), Dusk (https://brandsweets.com/palettes/cool#dusk), Blush (https://brandsweets.com/palettes/light#blush), Superhuman (https://brandsweets.com/colors/brands/superhuman-com). — https://brandsweets.com/colors/taupe
- **Teal** #008080 [harmony, pool: split] — Teal is a split-complement of #663a73: 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): 8.69:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.42:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9a5cad (4.51:1); AA: background → #bdbdbd (4.62:1); AAA: text → #b385c1 (7.04:1); AAA: background → #e8e8e8 (7.09:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/663a73-bd9fc1-adcb62-2d1f2a-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: "#663a73" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.