# #666397

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

## Values

- Hex: `#666397`
- RGB: rgb(102, 99, 151)
- HSL: hsl(243, 21%, 49%)
- OKLCH: oklch(0.524 0.081 285.9)
- Relative luminance: 0.1398
- Nearest named color: Bellflower (#5d66aa, Δ 3.136) — https://brandsweets.com/colors/bellflower
- Moods: cool, muted
- Page: https://brandsweets.com/colors/666397

## Tints & shades

- Tints (toward white): #7471a2, #8380ac, #9290b6, #a19fc1, #b0afcb, #bcbbd3, #cbcbdd, #dbdae7, #eae9f1, #f9f9fb
- Shades (toward black): #5d5b8b, #53517b, #4a496f, #403e60, #383653, #2d2c44, #252438, #1b1a28, #13121c, #08080c

## Harmonies

- Complementary: #959763
- Analogous: #637a97, #806397
- Triadic: #976563, #639765
- Split-complementary: #978063, #7a9763
- Tetradic: #97637a, #959763, #639780

## Colors that go with #666397

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 #666397: softer than #000 and cool enough to feel like part of the same palette. Seen in: Campus (https://brandsweets.com/palettes/friendly#campus), Harbour (https://brandsweets.com/palettes/cool#harbour), Amazon (https://brandsweets.com/colors/brands/amazon-com), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #666397: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Subaru (https://brandsweets.com/colors/brands/subaru-com). — https://brandsweets.com/colors/seagreen
- **Amber** #ffbf00 [pool] — Amber is paired with #666397 in 6 real palettes, including Warner Bros.'s brand system and McDonald's's brand system, as the accent. Seen in: Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #666397: 7 real palettes, including Fintech Trust and Ink & Paper, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Ink & Paper (https://brandsweets.com/palettes/minimal#ink-and-paper), Glacier (https://brandsweets.com/palettes/cool#glacier), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #666397 in 15 real palettes, including Marvel's brand system and Retro Pop, as the accent. Seen in: Marvel (https://brandsweets.com/colors/brands/marvel-com), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Netflix (https://brandsweets.com/colors/brands/netflix). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #666397: 4 real palettes, including Deep Water and Venmo's brand system, as the lead colour. Seen in: Deep Water (https://brandsweets.com/palettes/dark#deep-water), Venmo (https://brandsweets.com/colors/brands/venmo-com), Astro (https://brandsweets.com/colors/brands/astro-build), Calm (https://brandsweets.com/colors/brands/calm-com). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #666397: 10 real palettes, including Campus and The New York Times's brand system, as the lead colour. Seen in: Campus (https://brandsweets.com/palettes/friendly#campus), The New York Times (https://brandsweets.com/colors/brands/nytimes-com), HP (https://brandsweets.com/colors/brands/hp-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #666397: 5 real palettes, including Honda's brand system and Campbell's's brand system, as the supporting colour. Seen in: Honda (https://brandsweets.com/colors/brands/honda-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com), AT&T (https://brandsweets.com/colors/brands/att-com), Wendy's (https://brandsweets.com/colors/brands/wendys-com). — https://brandsweets.com/colors/firebrick

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

- On white (#ffffff): 5.53:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #55537f (7.17:1)
- On black (#000000): 3.8:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #7471a2 (4.63:1); AA: background → #e8e8e8 (4.51:1); AAA: text → #9593b8 (7.14:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/666397-a39cc4-dfa04e-261f2d-e9edf1?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: "#666397" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.