# #663c90

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

## Values

- Hex: `#663c90`
- RGB: rgb(102, 60, 144)
- HSL: hsl(270, 41%, 40%)
- OKLCH: oklch(0.447 0.136 304.6)
- Relative luminance: 0.0807
- Nearest named color: Lords of the Night (#664488, Δ 2.523) — https://brandsweets.com/colors/lords-of-the-night
- Moods: cool, modern
- Page: https://brandsweets.com/colors/663c90

## Tints & shades

- Tints (toward white): #7545a5, #8552b7, #9164be, #a17ac7, #b090d0, #bfa5d9, #cfbbe2, #dbcdea, #ebe2f3, #faf8fc
- Shades (toward black): #5c3681, #543277, #4a2c68, #42275d, #38214f, #2e1b41, #261736, #1c1128, #140c1d, #0a060e

## Harmonies

- Complementary: #66903c
- Analogous: #3c3c90, #903c90
- Triadic: #90663c, #3c9066
- Split-complementary: #90903c, #3c903c
- Tetradic: #903c3c, #66903c, #3c9090

## Colors that go with #663c90

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 #663c90: 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). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [pool] — Crimson is paired with #663c90 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), Gemstone (https://brandsweets.com/palettes/vivid#gemstone). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #663c90: 6 real palettes, including Slack's brand system and Hinge's brand system, as the lead colour. Seen in: Slack (https://brandsweets.com/colors/brands/slack-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), 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] — 7 real palettes, including Kraken's brand system and First Snow put Midnight Blue beside #663c90, 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), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono). — https://brandsweets.com/colors/midnightblue
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #663c90 in 5 real palettes, including Wayfair's brand system and Fivetran blue's brand system, as the supporting colour. Seen in: Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com), Nokia (https://brandsweets.com/colors/brands/nokia-com), Stripe (https://brandsweets.com/colors/brands/stripe). — https://brandsweets.com/colors/royalblue
- **Tomato** #ff6347 [pool] — 6 real palettes, including FedEx's brand system and Golden Hour put Tomato beside #663c90, as the supporting colour. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), Golden Hour (https://brandsweets.com/palettes/warm#golden-hour), GitLab (https://brandsweets.com/colors/brands/gitlab), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com). — https://brandsweets.com/colors/tomato
- **Dark Olive Green** #556b2f [harmony: complementary] — Dark Olive Green sits directly opposite #663c90 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 #663c90, 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

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

- On white (#ffffff): 8.03:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.61:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8f61bd (4.61:1); AA: background → #c2c2c2 (4.51:1); AAA: text → #ab88cd (7.13:1); AAA: background → #f0f0f0 (7.05:1)

## Brands using this color

- **Ledger** — secondary #6a3794 (Δ 1.461) — https://brandsweets.com/colors/brands/ledger-com

## 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/663c90-b59cc4-c9cb62-2c1f2d-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: "#663c90" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.