# #663d8a

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

## Values

- Hex: `#663d8a`
- RGB: rgb(102, 61, 138)
- HSL: hsl(272, 39%, 39%)
- OKLCH: oklch(0.445 0.127 306.5)
- Relative luminance: 0.08
- Nearest named color: Lords of the Night (#664488, Δ 1.821) — https://brandsweets.com/colors/lords-of-the-night
- Moods: cool, modern
- Page: https://brandsweets.com/colors/663d8a

## Tints & shades

- Tints (toward white): #7646a0, #8551b3, #9467bc, #a37cc5, #b291cf, #bea3d7, #cdb8e0, #dccde9, #ebe3f3, #faf8fc
- Shades (toward black): #5e3880, #543271, #4c2d67, #412759, #3a224e, #2f1c40, #271735, #1d1127, #150c1c, #0a060e

## Harmonies

- Complementary: #618a3d
- Analogous: #3f3d8a, #8a3d88
- Triadic: #8a663d, #3d8a66
- Split-complementary: #888a3d, #3d8a3f
- Tetradic: #8a3f3d, #618a3d, #3d888a

## Colors that go with #663d8a

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 #663d8a: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Harbour (https://brandsweets.com/palettes/cool#harbour), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com). — https://brandsweets.com/colors/charcoal
- **Denim** #1560bd [pool] — Designers have shipped Denim with #663d8a: 5 real palettes, including Hinge's brand system and Slack's brand system, as the accent. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Slack (https://brandsweets.com/colors/brands/slack-com), HP (https://brandsweets.com/colors/brands/hp-com), Linkedin (https://brandsweets.com/colors/brands/linkedin-com). — https://brandsweets.com/colors/denim
- **Midnight Blue** #191970 [pool] — 5 real palettes, including Kraken's brand system and First Snow put Midnight Blue beside #663d8a, as the lead colour. Seen in: Kraken (https://brandsweets.com/colors/brands/kraken-com), First Snow (https://brandsweets.com/palettes/cool#first-snow), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Lufthansa (https://brandsweets.com/colors/brands/lufthansa-com). — https://brandsweets.com/colors/midnightblue
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #663d8a in 6 real palettes, including Wayfair's brand system and Stripe's brand system, as the supporting colour. Seen in: Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Stripe (https://brandsweets.com/colors/brands/stripe), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com), Console Light (https://brandsweets.com/palettes/technical#console-light). — https://brandsweets.com/colors/royalblue
- **Tomato** #ff6347 [pool] — 6 real palettes, including Golden Hour and FedEx's brand system put Tomato beside #663d8a, as the supporting colour. Seen in: Golden Hour (https://brandsweets.com/palettes/warm#golden-hour), FedEx (https://brandsweets.com/colors/brands/fedex-com), GitLab (https://brandsweets.com/colors/brands/gitlab), Harley-Davidson (https://brandsweets.com/colors/brands/harley-davidson-com). — https://brandsweets.com/colors/tomato
- **Dark Olive Green** #556b2f [harmony: complementary] — Dark Olive Green sits directly opposite #663d8a on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/darkolivegreen
- **Blue** #0000ff [pool] — 3 real palettes, including Zillow's brand system and CVS's brand system put Blue beside #663d8a, as the lead colour. Seen in: Zillow (https://brandsweets.com/colors/brands/zillow-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #663d8a in 3 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). — https://brandsweets.com/colors/crimson

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

- On white (#ffffff): 8.08:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.6:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8f5fb9 (4.51:1); AA: background → #c2c2c2 (4.54:1); AAA: text → #ad8acc (7.28:1); AAA: background → #f0f0f0 (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/663d8a-b69cc4-c5cb62-2d1f2d-eae9f1?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: "#663d8a" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.