# #666fa9

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

## Values

- Hex: `#666fa9`
- RGB: rgb(102, 111, 169)
- HSL: hsl(232, 28%, 53%)
- OKLCH: oklch(0.559 0.091 276.3)
- Relative luminance: 0.1706
- Nearest named color: Loch Ness (#5f6db0, Δ 1.666) — https://brandsweets.com/colors/loch-ness
- Moods: cool, muted
- Page: https://brandsweets.com/colors/666fa9

## Tints & shades

- Tints (toward white): #767eb2, #838ab9, #939ac2, #a0a6ca, #b1b5d3, #bec2da, #ced1e3, #dbddeb, #ebedf4, #f8f9fb
- Shades (toward black): #58619d, #4f578c, #464d7c, #3d436c, #353b5f, #2c314e, #23273e, #1a1c2e, #11121d, #07080d

## Harmonies

- Complementary: #a9a066
- Analogous: #6690a9, #7e66a9
- Triadic: #a9666f, #6fa966
- Split-complementary: #a97e66, #90a966
- Tetradic: #a96690, #a9a066, #66a97e

## Colors that go with #666fa9

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 #666fa9: softer than #000 and cool enough to feel like part of the same palette. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), Campus (https://brandsweets.com/palettes/friendly#campus), Bloomberg (https://brandsweets.com/colors/brands/bloomberg-com), Hermès (https://brandsweets.com/colors/brands/hermes-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #666fa9 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), 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). — https://brandsweets.com/colors/seagreen
- **Amber** #ffbf00 [pool] — Amber is paired with #666fa9 in 8 real palettes, including Lemon Squeezy's brand system and Wired's brand system, as the lead colour. Seen in: Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Wired (https://brandsweets.com/colors/brands/wired-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 4 real palettes, including Pixar's brand system and Activision's brand system put Blue beside #666fa9, as the accent. Seen in: Pixar (https://brandsweets.com/colors/brands/pixar-com), Activision (https://brandsweets.com/colors/brands/activision-com), Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Readymag (https://brandsweets.com/colors/brands/readymag-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #666fa9: 8 real palettes, including Fintech Trust and Glacier, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #666fa9: 4 real palettes, including Dusk and Notion's brand system, as the accent. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Notion (https://brandsweets.com/colors/brands/notion), Riverbed (https://brandsweets.com/palettes/muted#riverbed), Atelier (https://brandsweets.com/palettes/elegant#atelier). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #666fa9 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), NASCAR (https://brandsweets.com/colors/brands/nascar-com), State Farm (https://brandsweets.com/colors/brands/statefarm-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #666fa9: 6 real palettes, including Astro's brand system and Deep Water, as the supporting colour. Seen in: Astro (https://brandsweets.com/colors/brands/astro-build), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Venmo (https://brandsweets.com/colors/brands/venmo-com), Telegram (https://brandsweets.com/colors/brands/telegram-org). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 4.76:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #4d5589 (7.06:1)
- On black (#000000): 4.41:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #6972ab (4.6:1); AA: background → #fafafa (4.56:1); AAA: text → #8d93bf (7.06:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/666fa9-9c9dc4-df864e-231f2d-e9eef1?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: "#666fa9" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.