# #307fd9

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

## Values

- Hex: `#307fd9`
- RGB: rgb(48, 127, 217)
- HSL: hsl(212, 69%, 52%)
- OKLCH: oklch(0.594 0.157 254.3)
- Relative luminance: 0.2082
- Nearest named color: Blue Jay (#5588dd, Δ 4.282) — https://brandsweets.com/colors/blue-jay
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/307fd9

## Tints & shades

- Tints (toward white): #468cdd, #5797e0, #6ca4e4, #7eafe7, #93bceb, #a9caef, #bad4f2, #d0e2f6, #e1ecf9, #f6fafd
- Shades (toward black): #2572cb, #2166b5, #1e5ca4, #1a508e, #164479, #123863, #0e2c4e, #0b223c, #071627, #030a11

## Harmonies

- Complementary: #d98a30
- Analogous: #30d3d9, #3630d9
- Triadic: #d9307f, #7fd930
- Split-complementary: #d93630, #d3d930
- Tetradic: #d930d3, #d98a30, #30d936

## Colors that go with #307fd9

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 #307fd9: softer than #000 and cool enough to feel like part of the same palette. Seen in: Disney (https://brandsweets.com/colors/brands/disney-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #307fd9 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: NASCAR (https://brandsweets.com/colors/brands/nascar-com), Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com), Foot Locker (https://brandsweets.com/colors/brands/footlocker-com), State Farm (https://brandsweets.com/colors/brands/statefarm-com). — https://brandsweets.com/colors/crimson
- **Copper** #b87333 [harmony, pool: complementary] — Copper sits directly opposite #307fd9 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Notion (https://brandsweets.com/colors/brands/notion). — https://brandsweets.com/colors/copper
- **Amber** #ffbf00 [pool] — Amber is paired with #307fd9 in 12 real palettes, including Walmart's brand system and Google's brand system, as the accent. Seen in: Walmart (https://brandsweets.com/colors/brands/walmart-com), Google (https://brandsweets.com/colors/brands/google-com), Wired (https://brandsweets.com/colors/brands/wired-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 14 real palettes, including Readymag's brand system and Qualcomm's brand system put Blue beside #307fd9, as the supporting colour. Seen in: Readymag (https://brandsweets.com/colors/brands/readymag-com), Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), BBC (https://brandsweets.com/colors/brands/bbc-com), Cargo (https://brandsweets.com/colors/brands/cargo-site). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #307fd9: 11 real palettes, including Hershey's's brand system and Carrefour's brand system, as the supporting colour. Seen in: Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Carrefour (https://brandsweets.com/colors/brands/carrefour-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com), Intel (https://brandsweets.com/colors/brands/intel-com). — https://brandsweets.com/colors/cobalt
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #307fd9: 9 real palettes, including Patreon's brand system and Astro's brand system, as the supporting colour. Seen in: Patreon (https://brandsweets.com/colors/brands/patreon-com), Astro (https://brandsweets.com/colors/brands/astro-build), Telegram (https://brandsweets.com/colors/brands/telegram-org), Venmo (https://brandsweets.com/colors/brands/venmo-com). — https://brandsweets.com/colors/deepskyblue
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #307fd9: 6 real palettes, including Honda's brand system and AT&T's brand system, as the supporting colour. Seen in: Honda (https://brandsweets.com/colors/brands/honda-com), AT&T (https://brandsweets.com/colors/brands/att-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com), Wendy's (https://brandsweets.com/colors/brands/wendys-com). — https://brandsweets.com/colors/firebrick

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

- On white (#ffffff): 4.07:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2777d3 (4.5:1); AA: background → #141414 (4.53:1); AAA: text → #1c589b (7.2:1)
- On black (#000000): 5.16:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #5b9ae1 (7.15:1)

## Brands using this color

- **Notion** — accent #2383e2 (Δ 1.604) — https://brandsweets.com/colors/brands/notion
- **Substack** — secondary #0083d5 (Δ 1.988) — https://brandsweets.com/colors/brands/substack-com

## 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/307fd9-9caac4-df564e-1f202d-e9f1f1?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: "#307fd9" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.