# #666ff5

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

## Values

- Hex: `#666ff5`
- RGB: rgb(102, 111, 245)
- HSL: hsl(236, 88%, 68%)
- OKLCH: oklch(0.606 0.197 275.9)
- Relative luminance: 0.2079
- Nearest named color: Blue Öyster Cult (#5577ee, Δ 2.861) — https://brandsweets.com/colors/blue-oyster-cult
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/666ff5

## Tints & shades

- Tints (toward white): #747df6, #828af7, #9198f8, #9fa5f9, #aeb3fa, #bcc0fb, #cacefc, #d9dbfd, #e7e9fd, #f5f6fe
- Shades (toward black): #4954f3, #2735f1, #0f1eeb, #0d19c9, #0b16ad, #091290, #070e6e, #050a51, #030630, #010213

## Harmonies

- Complementary: #f5ec66
- Analogous: #66b7f5, #a466f5
- Triadic: #f5666f, #6ff566
- Split-complementary: #f5a466, #b7f566
- Tetradic: #f566b7, #f5ec66, #66f5a4

## Colors that go with #666ff5

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 #666ff5: softer than #000 and cool enough to feel like part of the same palette. Seen in: Docker (https://brandsweets.com/colors/brands/docker-com), Disney (https://brandsweets.com/colors/brands/disney-com), Zoom (https://brandsweets.com/colors/brands/zoom-us), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #666ff5 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Subaru (https://brandsweets.com/colors/brands/subaru-com), Next.js (https://brandsweets.com/colors/brands/nextjs-org), Intel (https://brandsweets.com/colors/brands/intel-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/seagreen
- **Amber** #ffbf00 [pool] — Amber is paired with #666ff5 in 8 real palettes, including Mastodon hosted on mastodon.social's brand system and Google's brand system, as the accent. Seen in: Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social), Google (https://brandsweets.com/colors/brands/google-com), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Walmart (https://brandsweets.com/colors/brands/walmart-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 13 real palettes, including Qualcomm's brand system and Penpot's brand system put Blue beside #666ff5, as the accent. Seen in: Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Penpot (https://brandsweets.com/colors/brands/penpot-app), Cargo (https://brandsweets.com/colors/brands/cargo-site), Samsung (https://brandsweets.com/colors/brands/samsung-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #666ff5: 8 real palettes, including Behance's brand system and Carrefour's brand system, as the supporting colour. Seen in: Behance (https://brandsweets.com/colors/brands/behance-net), Carrefour (https://brandsweets.com/colors/brands/carrefour-com), Nokia (https://brandsweets.com/colors/brands/nokia-com), Nivea (https://brandsweets.com/colors/brands/nivea-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #666ff5 in 12 real palettes, including Behance's brand system and WWE's brand system, as the accent. Seen in: Behance (https://brandsweets.com/colors/brands/behance-net), WWE (https://brandsweets.com/colors/brands/wwe-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Toyota (https://brandsweets.com/colors/brands/toyota-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #666ff5: 8 real palettes, including Calm's brand system and Elastic's brand system, as the lead colour. Seen in: Calm (https://brandsweets.com/colors/brands/calm-com), Elastic (https://brandsweets.com/colors/brands/elastic-co), Patreon (https://brandsweets.com/colors/brands/patreon-com), Blueprint (https://brandsweets.com/palettes/technical#blueprint). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #666ff5: 15 real palettes, including Fivetran blue's brand system and Coursera's brand system, as the supporting colour. Seen in: Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com), Coursera (https://brandsweets.com/colors/brands/coursera-org), Guinness (https://brandsweets.com/colors/brands/guinness-com), Square (https://brandsweets.com/colors/brands/squareup-com). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 4.07:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #5762f4 (4.71:1); AA: background → #141414 (4.52:1); AAA: text → #2c39f2 (7.06:1)
- On black (#000000): 5.16:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #878ff7 (7.3:1)

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- 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/666ff5-9e9cc4-df8f4e-241f2d-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: "#666ff5" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.