# #3f91de

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

## Values

- Hex: `#3f91de`
- RGB: rgb(63, 145, 222)
- HSL: hsl(209, 71%, 56%)
- OKLCH: oklch(0.642 0.14 249.8)
- Relative luminance: 0.2658
- Nearest named color: Blue Jay (#5588dd, Δ 2.769) — https://brandsweets.com/colors/blue-jay
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/3f91de

## Tints & shades

- Tints (toward white): #519be1, #62a5e4, #78b2e8, #89bceb, #9bc6ee, #acd0f1, #bedaf4, #d3e6f8, #e5f0fb, #f6fafe
- Shades (toward black): #2985db, #2278c9, #1e68ae, #1a5b99, #164e83, #12416d, #0f3457, #0a253d, #071727, #030a11

## Harmonies

- Complementary: #de8c3f
- Analogous: #3fdedc, #3f42de
- Triadic: #de3f91, #91de3f
- Split-complementary: #de3f42, #dedc3f
- Tetradic: #dc3fde, #de8c3f, #42de3f

## Colors that go with #3f91de

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 #3f91de: softer than #000 and cool enough to feel like part of the same palette. Seen in: Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Blizzard (https://brandsweets.com/colors/brands/blizzard-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 #3f91de 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 #3f91de 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), Wired (https://brandsweets.com/colors/brands/wired-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 9 real palettes, including Qualcomm's brand system and Readymag's brand system put Blue beside #3f91de, as the accent. Seen in: Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Unity (https://brandsweets.com/colors/brands/unity-com), Cargo (https://brandsweets.com/colors/brands/cargo-site). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #3f91de: 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 #3f91de 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 #3f91de 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 #3f91de: 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): 3.32:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2278c9 (4.57:1); AA: background → #262626 (4.55:1); AAA: text → #195994 (7.25:1)
- On black (#000000): 6.32:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #519be1 (7.13:1)

## 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/3f91de-9cacc4-df4e4e-1f212d-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: "#3f91de" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.