# #537ee9

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

## Values

- Hex: `#537ee9`
- RGB: rgb(83, 126, 233)
- HSL: hsl(223, 77%, 62%)
- OKLCH: oklch(0.616 0.168 265.3)
- Relative luminance: 0.2264
- Nearest named color: Blue Öyster Cult (#5577ee, Δ 1.994) — https://brandsweets.com/colors/blue-oyster-cult
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/537ee9

## Tints & shades

- Tints (toward white): #668beb, #7396ed, #85a3ef, #93adf1, #a5bbf3, #b7c9f6, #c4d3f7, #d6e0fa, #e4ebfb, #f6f8fe
- Shades (toward black): #3869e5, #1d55e2, #1a4ccb, #1742b0, #133895, #102e7a, #0c245f, #091b48, #06112d, #020712

## Harmonies

- Complementary: #e9be53
- Analogous: #53c8e9, #7453e9
- Triadic: #e9537e, #7ee953
- Split-complementary: #e97453, #c8e953
- Tetradic: #e953c8, #e9be53, #53e974

## Colors that go with #537ee9

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 #537ee9: softer than #000 and cool enough to feel like part of the same palette. Seen in: Disney (https://brandsweets.com/colors/brands/disney-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Docker (https://brandsweets.com/colors/brands/docker-com), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #537ee9 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), NASCAR (https://brandsweets.com/colors/brands/nascar-com), Behance (https://brandsweets.com/colors/brands/behance-net). — https://brandsweets.com/colors/crimson
- **Amber** #ffbf00 [pool] — Amber is paired with #537ee9 in 13 real palettes, including Google's brand system and Heatwave, as the accent. Seen in: Google (https://brandsweets.com/colors/brands/google-com), Heatwave (https://brandsweets.com/palettes/warm#heatwave), Walmart (https://brandsweets.com/colors/brands/walmart-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 13 real palettes, including Qualcomm's brand system and Readymag's brand system put Blue beside #537ee9, as the accent. Seen in: Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), 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 #537ee9: 10 real palettes, including Carrefour's brand system and Behance's brand system, as the accent. Seen in: Carrefour (https://brandsweets.com/colors/brands/carrefour-com), Behance (https://brandsweets.com/colors/brands/behance-net), Intel (https://brandsweets.com/colors/brands/intel-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com). — https://brandsweets.com/colors/cobalt
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #537ee9: 10 real palettes, including Patreon's brand system and Venmo's brand system, as the supporting colour. Seen in: Patreon (https://brandsweets.com/colors/brands/patreon-com), Venmo (https://brandsweets.com/colors/brands/venmo-com), Astro (https://brandsweets.com/colors/brands/astro-build), Telegram (https://brandsweets.com/colors/brands/telegram-org). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #537ee9: 18 real palettes, including Coursera's brand system and Venmo's brand system, as the accent. Seen in: Coursera (https://brandsweets.com/colors/brands/coursera-org), Venmo (https://brandsweets.com/colors/brands/venmo-com), Guinness (https://brandsweets.com/colors/brands/guinness-com), Motorola (https://brandsweets.com/colors/brands/motorola-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #537ee9: 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), Bose (https://brandsweets.com/colors/brands/bose-com). — https://brandsweets.com/colors/firebrick

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

- On white (#ffffff): 3.8:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #3d6de6 (4.64:1); AA: background → #1a1a1a (4.58:1); AAA: text → #1a4ccb (7.14:1)
- On black (#000000): 5.53:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #7396ed (7.31:1)

## Brands using this color

- **Zed** — secondary #5c78e2 (Δ 1.832) — https://brandsweets.com/colors/brands/zed-dev

## 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/537ee9-9ca3c4-df704e-211f2d-e9eff1?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: "#537ee9" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.