# #4391df

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

## Values

- Hex: `#4391df`
- RGB: rgb(67, 145, 223)
- HSL: hsl(210, 71%, 57%)
- OKLCH: oklch(0.644 0.14 250.9)
- Relative luminance: 0.2677
- Nearest named color: Blue Jay (#5588dd, Δ 2.606) — https://brandsweets.com/colors/blue-jay
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/4391df

## Tints & shades

- Tints (toward white): #559ce2, #66a6e5, #78b0e8, #89baeb, #9fc7ef, #b1d1f2, #c2dbf5, #d3e6f8, #e5f0fb, #f6fafe
- Shades (toward black): #2e85dc, #2275c9, #1e69b3, #1b5c9d, #174f87, #12406d, #0f3357, #0b2641, #071727, #030a11

## Harmonies

- Complementary: #df9143
- Analogous: #43dfdf, #4343df
- Triadic: #df4391, #91df43
- Split-complementary: #df4343, #dfdf43
- Tetradic: #df43df, #df9143, #43df43

## Colors that go with #4391df

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 #4391df: softer than #000 and cool enough to feel like part of the same palette. Seen in: Blizzard (https://brandsweets.com/colors/brands/blizzard-com), Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Lido (https://brandsweets.com/palettes/vivid#lido), Dusty Blue (https://brandsweets.com/palettes/cool#dusty-blue). — https://brandsweets.com/colors/charcoal
- **Copper** #b87333 [harmony, pool: complementary] — Copper sits directly opposite #4391df 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), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/copper
- **Amber** #ffbf00 [pool] — Amber is paired with #4391df in 12 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), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Wired (https://brandsweets.com/colors/brands/wired-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 9 real palettes, including Qualcomm's brand system and Unity's brand system put Blue beside #4391df, as the accent. Seen in: Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Unity (https://brandsweets.com/colors/brands/unity-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Cargo (https://brandsweets.com/colors/brands/cargo-site). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #4391df: 6 real palettes, including Blue Mono and Hershey's's brand system, as the lead colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #4391df in 7 real palettes, including NASCAR's brand system and Pizza Hut's brand system, as the supporting colour. Seen in: NASCAR (https://brandsweets.com/colors/brands/nascar-com), Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), State Farm (https://brandsweets.com/colors/brands/statefarm-com). — https://brandsweets.com/colors/crimson
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #4391df in 4 real palettes, including Playground and Elastic's brand system, as the lead colour. Seen in: Playground (https://brandsweets.com/palettes/bold#playground), Elastic (https://brandsweets.com/colors/brands/elastic-co), Learning App (https://brandsweets.com/palettes/playful#learning-app), Ahrefs (https://brandsweets.com/colors/brands/ahrefs-com). — https://brandsweets.com/colors/darkorange
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #4391df: 9 real palettes, including Telegram's brand system and Patreon's brand system, as the lead colour. Seen in: Telegram (https://brandsweets.com/colors/brands/telegram-org), Patreon (https://brandsweets.com/colors/brands/patreon-com), Figma (https://brandsweets.com/colors/brands/figma), Venmo (https://brandsweets.com/colors/brands/venmo-com). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 3.3:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2378cd (4.53:1); AA: background → #262626 (4.58:1); AAA: text → #1a5999 (7.16:1)
- On black (#000000): 6.35:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #559ce2 (7.24:1)

## 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/4391df-9cabc4-df514e-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: "#4391df" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.