# #397ff9

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

## Values

- Hex: `#397ff9`
- RGB: rgb(57, 127, 249)
- HSL: hsl(218, 94%, 60%)
- OKLCH: oklch(0.618 0.196 260.7)
- Relative luminance: 0.2289
- Nearest named color: Azure (#007fff, Δ 2.288) — https://brandsweets.com/colors/azure-2
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/397ff9

## Tints & shades

- Tints (toward white): #4d8cf9, #6199fa, #70a3fb, #83affb, #97bcfc, #abc9fc, #bfd6fd, #cedffd, #e1ecfe, #f5f9ff
- Shades (toward black): #1b6cf8, #075ef2, #0752d5, #0649bc, #053d9e, #043281, #032868, #021d4a, #021331, #010814

## Harmonies

- Complementary: #f9b339
- Analogous: #39dff9, #5339f9
- Triadic: #f9397f, #7ff939
- Split-complementary: #f95339, #dff939
- Tetradic: #f939df, #f9b339, #39f953

## Colors that go with #397ff9

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 #397ff9: softer than #000 and cool enough to feel like part of the same palette. Seen in: Disney (https://brandsweets.com/colors/brands/disney-com), Docker (https://brandsweets.com/colors/brands/docker-com), Zoom (https://brandsweets.com/colors/brands/zoom-us), Blizzard (https://brandsweets.com/colors/brands/blizzard-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #397ff9 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Behance (https://brandsweets.com/colors/brands/behance-net), WWE (https://brandsweets.com/colors/brands/wwe-com), Foot Locker (https://brandsweets.com/colors/brands/footlocker-com), Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com). — https://brandsweets.com/colors/crimson
- **Amber** #ffbf00 [pool] — Amber is paired with #397ff9 in 10 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 Cargo's brand system and Samsung's brand system put Blue beside #397ff9, as the accent. Seen in: Cargo (https://brandsweets.com/colors/brands/cargo-site), Samsung (https://brandsweets.com/colors/brands/samsung-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Penpot (https://brandsweets.com/colors/brands/penpot-app). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #397ff9: 11 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), Nokia (https://brandsweets.com/colors/brands/nokia-com), Nivea (https://brandsweets.com/colors/brands/nivea-com). — https://brandsweets.com/colors/cobalt
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #397ff9: 10 real palettes, including Venmo's brand system and Patreon's brand system, as the supporting colour. Seen in: Venmo (https://brandsweets.com/colors/brands/venmo-com), Patreon (https://brandsweets.com/colors/brands/patreon-com), Elastic (https://brandsweets.com/colors/brands/elastic-co), Figma (https://brandsweets.com/colors/brands/figma). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #397ff9: 17 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), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #397ff9: 5 real palettes, including Bose's brand system and Honda's brand system, as the accent. Seen in: Bose (https://brandsweets.com/colors/brands/bose-com), Honda (https://brandsweets.com/colors/brands/honda-com), Nissan (https://brandsweets.com/colors/brands/nissanusa-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com). — https://brandsweets.com/colors/firebrick

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

- On white (#ffffff): 3.77:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #1b6cf8 (4.62:1); AA: background → #1c1c1c (4.53:1); AAA: text → #064ecb (7.09:1)
- On black (#000000): 5.58:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #5c96fa (7.2:1)

## Brands using this color

- **PostHog** — secondary #2f80fa (Δ 0.638) — https://brandsweets.com/colors/brands/posthog-com
- **Spline** — primary #4482fc (Δ 1.326) — https://brandsweets.com/colors/brands/spline-design
- **Coursera** — secondary #3286ff (Δ 1.844) — https://brandsweets.com/colors/brands/coursera-org
- **Bluesky Social** — primary #1484fc (Δ 1.9) — https://brandsweets.com/colors/brands/bsky-app

## Curated palettes containing it

- **Playground** (bold, playful, warm) — #ff8c00, #3b82f6, #22c55e, #fff8e7, #1d1d1d — Orange, blue and green — the colors of playground equipment; loud, cheerful, obviously for kids. — tool: https://brandsweets.com/palettes/new/ff8c00-3b82f6-22c55e-fff8e7-1d1d1d — collection: https://brandsweets.com/palettes/bold
- **Studio Grey** (minimal, muted, modern) — #1a1a1a, #8c8c8c, #3a86ff, #f2f2f2 — A pure greyscale with a single electric blue — the portfolio palette that makes work look considered. — tool: https://brandsweets.com/palettes/new/1a1a1a-8c8c8c-3a86ff-f2f2f2 — collection: https://brandsweets.com/palettes/minimal

## 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/397ff9-9ca6c4-df644e-201f2d-e9f0f1?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: "#397ff9" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.