# #377ef1

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

## Values

- Hex: `#377ef1`
- RGB: rgb(55, 126, 241)
- HSL: hsl(217, 87%, 58%)
- OKLCH: oklch(0.61 0.187 259.7)
- Relative luminance: 0.2208
- Nearest named color: Azure (#007fff, Δ 2.757) — https://brandsweets.com/colors/azure-2
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/377ef1

## Tints & shades

- Tints (toward white): #4a8af2, #5d97f4, #70a3f5, #83aff6, #96bcf8, #a9c8f9, #bcd4fa, #cfe0fc, #e2edfd, #f5f9fe
- Shades (toward black): #1f6fef, #1060e0, #0e55c8, #0c49ac, #0a3f94, #09357c, #07295f, #051e48, #03122b, #010813

## Harmonies

- Complementary: #f1aa37
- Analogous: #37dbf1, #4c37f1
- Triadic: #f1377e, #7ef137
- Split-complementary: #f14c37, #dbf137
- Tetradic: #f137db, #f1aa37, #37f14c

## Colors that go with #377ef1

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 #377ef1: softer than #000 and cool enough to feel like part of the same palette. Seen in: Disney (https://brandsweets.com/colors/brands/disney-com), Docker (https://brandsweets.com/colors/brands/docker-com), Zoom (https://brandsweets.com/colors/brands/zoom-us), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Crimson** #dc143c [harmony, pool: triadic] — Crimson completes a triad with #377ef1 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Behance (https://brandsweets.com/colors/brands/behance-net), Foot Locker (https://brandsweets.com/colors/brands/footlocker-com), WWE (https://brandsweets.com/colors/brands/wwe-com), Pizza Hut (https://brandsweets.com/colors/brands/pizzahut-com). — https://brandsweets.com/colors/crimson
- **Copper** #b87333 [harmony, pool: complementary] — Copper sits directly opposite #377ef1 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 #377ef1 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), Walmart (https://brandsweets.com/colors/brands/walmart-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 14 real palettes, including Readymag's brand system and Cargo's brand system put Blue beside #377ef1, as the supporting colour. Seen in: Readymag (https://brandsweets.com/colors/brands/readymag-com), Cargo (https://brandsweets.com/colors/brands/cargo-site), Samsung (https://brandsweets.com/colors/brands/samsung-com), Penpot (https://brandsweets.com/colors/brands/penpot-app). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #377ef1: 11 real palettes, including Carrefour's brand system and Behance's brand system, as the accent. Seen in: Carrefour (https://brandsweets.com/colors/brands/carrefour-com), Behance (https://brandsweets.com/colors/brands/behance-net), Nokia (https://brandsweets.com/colors/brands/nokia-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 #377ef1: 9 real palettes, including Patreon's brand system and Venmo's brand system, as the supporting colour. Seen in: Patreon (https://brandsweets.com/colors/brands/patreon-com), Venmo (https://brandsweets.com/colors/brands/venmo-com), Elastic (https://brandsweets.com/colors/brands/elastic-co), Astro (https://brandsweets.com/colors/brands/astro-build). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #377ef1: 18 real palettes, including Coursera's brand system and Guinness's brand system, as the accent. Seen in: Coursera (https://brandsweets.com/colors/brands/coursera-org), Guinness (https://brandsweets.com/colors/brands/guinness-com), Venmo (https://brandsweets.com/colors/brands/venmo-com), Fivetran blue (https://brandsweets.com/colors/brands/fivetran-com). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 3.88:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #1f6fef (4.59:1); AA: background → #171717 (4.62:1); AAA: text → #0d51bf (7.13:1)
- On black (#000000): 5.42:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #5d97f4 (7.2:1)

## Brands using this color

- **PostHog** — secondary #2f80fa (Δ 1.406) — https://brandsweets.com/colors/brands/posthog-com

## Curated palettes containing it

- **Playground** (bold, playful, warm) — #ff8c00, #3b82f6, #22c55e, #fff8e7, #1d1d1d — Orange, blue and green — the colors of playground equipment; loud, cheerful, obviously for kids. — tool: https://brandsweets.com/palettes/new/ff8c00-3b82f6-22c55e-fff8e7-1d1d1d — collection: https://brandsweets.com/palettes/bold

## 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/377ef1-9ca7c4-df624e-201f2d-e9f0f1?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: "#377ef1" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.