# #428a57

A color — neutral. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#428a57`
- RGB: rgb(66, 138, 87)
- HSL: hsl(138, 35%, 40%)
- OKLCH: oklch(0.573 0.107 151.2)
- Relative luminance: 0.2002
- Nearest named color: seagreen (#2e8b57, Δ 1.45) — https://brandsweets.com/colors/seagreen
- Moods: neutral
- Page: https://brandsweets.com/colors/428a57

## Tints & shades

- Tints (toward white): #4c9e65, #5aaf73, #6bb882, #80c293, #94cca5, #a9d6b6, #bee0c8, #cfe8d6, #e3f2e8, #f8fcf9
- Shades (toward black): #3c7c4f, #377248, #306440, #2b5a39, #244c30, #1e3e27, #193421, #122618, #0d1c12, #070e09

## Harmonies

- Complementary: #8a4274
- Analogous: #518a42, #428a7b
- Triadic: #58428a, #8a5842
- Split-complementary: #7b428a, #8a4251
- Tetradic: #42518a, #8a4274, #8a7b42

## Colors that go with #428a57

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 #428a57: softer than #000 and cool enough to feel like part of the same palette. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), N26 (https://brandsweets.com/colors/brands/n26-com), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool). — https://brandsweets.com/colors/charcoal
- **Royal Blue** #4169e1 [harmony, pool: triadic] — Royal Blue completes a triad with #428a57 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Subaru (https://brandsweets.com/colors/brands/subaru-com), Coinbase (https://brandsweets.com/colors/brands/coinbase), Console Light (https://brandsweets.com/palettes/technical#console-light), Telehealth (https://brandsweets.com/palettes/modern#telehealth). — https://brandsweets.com/colors/royalblue
- **Copper** #b87333 [pool] — Designers have shipped Copper with #428a57: 5 real palettes, including Wellness and Riverbed, as the supporting colour. Seen in: Wellness (https://brandsweets.com/palettes/warm#wellness), Riverbed (https://brandsweets.com/palettes/muted#riverbed), Clean Beauty (https://brandsweets.com/palettes/minimal#clean-beauty), Clay & Linen (https://brandsweets.com/palettes/warm#clay-and-linen). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #428a57 in 7 real palettes, including Five Guys's brand system and Netflix's brand system, as the supporting colour. Seen in: Five Guys (https://brandsweets.com/colors/brands/fiveguys-com), Netflix (https://brandsweets.com/colors/brands/netflix), Coinbase (https://brandsweets.com/colors/brands/coinbase), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #428a57: 6 real palettes, including Intel's brand system and Jack Daniel's's brand system, as the supporting colour. Seen in: Intel (https://brandsweets.com/colors/brands/intel-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/denim
- **Midnight Blue** #191970 [pool] — 4 real palettes, including Paramount+'s brand system and Tide Pool put Midnight Blue beside #428a57, as the supporting colour. Seen in: Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool), Telehealth (https://brandsweets.com/palettes/modern#telehealth), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/midnightblue
- **Rust** #b7410e [harmony, pool: triadic] — Rust completes a triad with #428a57 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre), Gallery (https://brandsweets.com/palettes/editorial#gallery), Harvest (https://brandsweets.com/palettes/warm#harvest). — https://brandsweets.com/colors/rust
- **Sage Green** #9caf88 [pool] — Designers have shipped Sage Green with #428a57: 4 real palettes, including Forest Floor and Riverbed, as the lead colour. Seen in: Forest Floor (https://brandsweets.com/palettes/dark#forest-floor), Riverbed (https://brandsweets.com/palettes/muted#riverbed), Olive Grove (https://brandsweets.com/palettes/muted#olive-grove), Graphite (https://brandsweets.com/palettes/technical#graphite). — https://brandsweets.com/colors/sage-green

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

- On white (#ffffff): 4.2:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #3f8353 (4.58:1); AA: background → #0f0f0f (4.57:1); AAA: text → #2e603d (7.35:1)
- On black (#000000): 5:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #51a96b (7.24:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/428a57-a2beae-be59d4-1f2d29-ebf1e9?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: "#428a57" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.