# #665bb9

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

## Values

- Hex: `#665bb9`
- RGB: rgb(102, 91, 185)
- HSL: hsl(247, 40%, 54%)
- OKLCH: oklch(0.528 0.143 285.7)
- Relative luminance: 0.1381
- Nearest named color: slateblue (#6a5acd, Δ 3.21) — https://brandsweets.com/colors/slateblue
- Moods: cool, modern
- Page: https://brandsweets.com/colors/665bb9

## Tints & shades

- Tints (toward white): #7369bf, #847bc6, #9189cd, #a29bd4, #afa9da, #bcb8e0, #cdc9e8, #dad8ee, #ebeaf6, #f8f8fc
- Shades (toward black): #574baf, #4e439d, #453c8b, #3c3479, #332c68, #2a2556, #221d44, #191532, #100e20, #07060e

## Harmonies

- Complementary: #aeb95b
- Analogous: #5b7fb9, #955bb9
- Triadic: #b9665b, #5bb966
- Split-complementary: #b9955b, #7fb95b
- Tetradic: #b95b7f, #aeb95b, #5bb995

## Colors that go with #665bb9

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 #665bb9: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Starlink (https://brandsweets.com/colors/brands/starlink-com), Amazon (https://brandsweets.com/colors/brands/amazon-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #665bb9: 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), Next.js (https://brandsweets.com/colors/brands/nextjs-org). — https://brandsweets.com/colors/seagreen
- **Amber** #ffbf00 [pool] — Amber is paired with #665bb9 in 8 real palettes, including Warner Bros.'s brand system and Wikipedia's brand system, as the accent. Seen in: Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org), NBA (https://brandsweets.com/colors/brands/nba-com), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 8 real palettes, including Pixar's brand system and Activision's brand system put Blue beside #665bb9, 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), Tesco (https://brandsweets.com/colors/brands/tesco-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #665bb9: 10 real palettes, including Fintech Trust and Unilever's brand system, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Unilever (https://brandsweets.com/colors/brands/unilever-com), Intel (https://brandsweets.com/colors/brands/intel-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/cobalt
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #665bb9: 6 real palettes, including Coca-Cola's brand system and NBA's brand system, as the supporting colour. Seen in: Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), NBA (https://brandsweets.com/colors/brands/nba-com), Gopro (https://brandsweets.com/colors/brands/gopro-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #665bb9 in 16 real palettes, including Marvel's brand system and Netflix's brand system, as the accent. Seen in: Marvel (https://brandsweets.com/colors/brands/marvel-com), Netflix (https://brandsweets.com/colors/brands/netflix), Ulta Beauty (https://brandsweets.com/colors/brands/ulta-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #665bb9: 5 real palettes, including Calm's brand system and Astro's brand system, as the lead colour. Seen in: Calm (https://brandsweets.com/colors/brands/calm-com), Astro (https://brandsweets.com/colors/brands/astro-build), Venmo (https://brandsweets.com/colors/brands/venmo-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 5.58:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #5549ab (7.17:1)
- On black (#000000): 3.76:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #7369bf (4.5:1); AA: background → #e8e8e8 (4.56:1); AAA: text → #9890d0 (7.24:1)

## Brands using this color

- **Sentry** — secondary #6a5fc1 (Δ 1.673) — https://brandsweets.com/colors/brands/sentry-io

## 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/665bb9-a59cc4-dfaa4e-271f2d-e9ecf1?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: "#665bb9" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.