# #3f558d

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

## Values

- Hex: `#3f558d`
- RGB: rgb(63, 85, 141)
- HSL: hsl(223, 38%, 40%)
- OKLCH: oklch(0.459 0.096 266.5)
- Relative luminance: 0.0948
- Nearest named color: Dusk (#4e5481, Δ 2.712) — https://brandsweets.com/colors/dusk
- Moods: cool, modern
- Page: https://brandsweets.com/colors/3f558d

## Tints & shades

- Tints (toward white): #4962a2, #5670b3, #687fbb, #7d91c5, #92a3ce, #a7b5d7, #bcc7e1, #ced5e9, #e3e7f2, #f8f9fc
- Shades (toward black): #394d7f, #344674, #2e3e66, #29375b, #232f4d, #1c263f, #182035, #111727, #0d111c, #06090e

## Harmonies

- Complementary: #8d773f
- Analogous: #3f7c8d, #503f8d
- Triadic: #8d3f55, #558d3f
- Split-complementary: #8d503f, #7c8d3f
- Tetradic: #8d3f7c, #8d773f, #3f8d50

## Colors that go with #3f558d

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 #3f558d: softer than #000 and cool enough to feel like part of the same palette. Seen in: Harbour (https://brandsweets.com/palettes/cool#harbour), Amazon (https://brandsweets.com/colors/brands/amazon-com), Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #3f558d — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: 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), Subaru (https://brandsweets.com/colors/brands/subaru-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3f558d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Capital One (https://brandsweets.com/colors/brands/capitalone-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Discover (https://brandsweets.com/colors/brands/discover-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #3f558d in 4 real palettes, including McDonald's's brand system and Warner Bros.'s brand system, as the lead colour. Seen in: McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 6 real palettes, including Tesco's brand system and CVS's brand system put Blue beside #3f558d, as the supporting colour. Seen in: Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Activision (https://brandsweets.com/colors/brands/activision-com), Pixar (https://brandsweets.com/colors/brands/pixar-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f558d in 15 real palettes, including Walgreens's brand system and Costco's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Costco (https://brandsweets.com/colors/brands/costco-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Target : Expect More. Pay Less. (https://brandsweets.com/colors/brands/target-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #3f558d: 4 real palettes, including Venmo's brand system and Lamborghini's brand system, as the supporting colour. Seen in: Venmo (https://brandsweets.com/colors/brands/venmo-com), Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Astro (https://brandsweets.com/colors/brands/astro-build). — https://brandsweets.com/colors/deepskyblue
- **Dodger Blue** #1e90ff [pool] — Designers have shipped Dodger Blue with #3f558d: 4 real palettes, including Venmo's brand system and Apple's brand system, as the lead colour. Seen in: Venmo (https://brandsweets.com/colors/brands/venmo-com), Apple (https://brandsweets.com/colors/brands/apple-com), Coursera (https://brandsweets.com/colors/brands/coursera-org), HashiCorp (https://brandsweets.com/colors/brands/hashicorp-com). — https://brandsweets.com/colors/dodgerblue

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

- On white (#ffffff): 7.25:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.9:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5a73b5 (4.55:1); AA: background → #cccccc (4.52:1); AAA: text → #8497c8 (7.24:1); AAA: background → #fcfcfc (7.07:1)

## Fonts for this mood

- 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/3f558d-9ca3c4-df704e-211f2d-e9eff1?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: "#3f558d" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.