# #378cd2

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

## Values

- Hex: `#378cd2`
- RGB: rgb(55, 140, 210)
- HSL: hsl(207, 63%, 52%)
- OKLCH: oklch(0.621 0.133 247.1)
- Relative luminance: 0.2422
- Nearest named color: Blue Jay (#5588dd, Δ 3.283) — https://brandsweets.com/colors/blue-jay
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/378cd2

## Tints & shades

- Tints (toward white): #4c98d6, #5da2da, #72aedf, #82b7e3, #97c3e7, #accfec, #bcd9f0, #d1e5f5, #e2eef8, #f7fafd
- Shades (toward black): #2c7fc3, #2872af, #24679e, #1f5989, #1a4c74, #163e60, #11314b, #0d263a, #081825, #040b11

## Harmonies

- Complementary: #d27d37
- Analogous: #37d2ca, #373fd2
- Triadic: #d2378c, #8cd237
- Split-complementary: #d2373f, #d2ca37
- Tetradic: #ca37d2, #d27d37, #3fd237

## Colors that go with #378cd2

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 #378cd2: 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), Disney (https://brandsweets.com/colors/brands/disney-com), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #378cd2 — 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), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com), State Farm (https://brandsweets.com/colors/brands/statefarm-com). — https://brandsweets.com/colors/crimson
- **Copper** #b87333 [harmony, pool: complementary] — Copper sits directly opposite #378cd2 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 #378cd2 in 14 real palettes, including Wired's brand system and Google's brand system, as the accent. Seen in: Wired (https://brandsweets.com/colors/brands/wired-com), Google (https://brandsweets.com/colors/brands/google-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Heatwave (https://brandsweets.com/palettes/warm#heatwave). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 11 real palettes, including Qualcomm's brand system and Readymag's brand system put Blue beside #378cd2, 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 #378cd2: 8 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
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #378cd2 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 #378cd2: 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), Venmo (https://brandsweets.com/colors/brands/venmo-com). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 3.59:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2a7abb (4.57:1); AA: background → #1f1f1f (4.59:1); AAA: text → #205c8d (7.05:1)
- On black (#000000): 5.84:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #509bd7 (7.01:1)

## Brands using this color

- **Telegram** — secondary #318fd3 (Δ 0.824) — 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/378cd2-9cadc4-df4e53-1f212d-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: "#378cd2" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.