# #378fcd

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

## Values

- Hex: `#378fcd`
- RGB: rgb(55, 143, 205)
- HSL: hsl(205, 60%, 51%)
- OKLCH: oklch(0.626 0.125 243.3)
- Relative luminance: 0.2486
- Nearest named color: Blue Burst (#309cd0, Δ 3.576) — https://brandsweets.com/colors/blue-burst
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/378fcd

## Tints & shades

- Tints (toward white): #4b9ad2, #5ca3d6, #70afdb, #85bae0, #99c6e5, #a9cfea, #bedaef, #d2e6f4, #e2eff8, #f7fafd
- Shades (toward black): #2f81bc, #2b76ab, #266897, #215a83, #1d4f72, #17415e, #123249, #0d2435, #091925, #040b10

## Harmonies

- Complementary: #cd7637
- Analogous: #37cdc1, #3744cd
- Triadic: #cd378f, #8fcd37
- Split-complementary: #cd3744, #cdc137
- Tetradic: #c137cd, #cd7637, #44cd37

## Colors that go with #378fcd

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 #378fcd: softer than #000 and cool enough to feel like part of the same palette. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Dusty Blue (https://brandsweets.com/palettes/cool#dusty-blue), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Copper** #b87333 [harmony, pool: complementary] — Copper sits directly opposite #378fcd 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 #378fcd in 13 real palettes, including Beach Hut and Wired's brand system, as the supporting colour. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Wired (https://brandsweets.com/colors/brands/wired-com), Google (https://brandsweets.com/colors/brands/google-com), Heatwave (https://brandsweets.com/palettes/warm#heatwave). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 8 real palettes, including Qualcomm's brand system and Readymag's brand system put Blue beside #378fcd, 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 #378fcd: 7 real palettes, including Hershey's's brand system and Glacier, as the supporting colour. Seen in: Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Glacier (https://brandsweets.com/palettes/cool#glacier), General Mills (https://brandsweets.com/colors/brands/generalmills-com), Intel (https://brandsweets.com/colors/brands/intel-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #378fcd in 10 real palettes, including NASCAR's brand system and Retro Pop, as the supporting colour. Seen in: NASCAR (https://brandsweets.com/colors/brands/nascar-com), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Wendy's (https://brandsweets.com/colors/brands/wendys-com), State Farm (https://brandsweets.com/colors/brands/statefarm-com). — https://brandsweets.com/colors/crimson
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #378fcd in 4 real palettes, including Elastic's brand system and Playground, as the lead colour. Seen in: Elastic (https://brandsweets.com/colors/brands/elastic-co), Playground (https://brandsweets.com/palettes/bold#playground), 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 #378fcd: 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), Astro (https://brandsweets.com/colors/brands/astro-build), Figma (https://brandsweets.com/colors/brands/figma). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 3.52:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2d7bb4 (4.56:1); AA: background → #212121 (4.58:1); AAA: text → #225d87 (7.04:1)
- On black (#000000): 5.97:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #509cd3 (7.04:1)

## Brands using this color

- **Telegram** — secondary #318fd3 (Δ 0.953) — https://brandsweets.com/colors/brands/telegram-org

## 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/378fcd-9cafc4-df4e58-1f212d-e9f1f0?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: "#378fcd" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.