# #51639a

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

## Values

- Hex: `#51639a`
- RGB: rgb(81, 99, 154)
- HSL: hsl(225, 31%, 46%)
- OKLCH: oklch(0.51 0.09 269.3)
- Relative luminance: 0.1301
- Nearest named color: Bellflower (#5d66aa, Δ 3.156) — https://brandsweets.com/colors/bellflower
- Moods: cool, muted
- Page: https://brandsweets.com/colors/51639a

## Tints & shades

- Tints (toward white): #5b6fa9, #6c7db2, #808fbc, #919ec5, #a1adce, #b2bbd7, #c3cadf, #d7dcea, #e8eaf3, #f8f9fb
- Shades (toward black): #4a5a8c, #43527f, #3a476e, #333e61, #2c3654, #252d46, #1e2539, #151a28, #0e111b, #07090d

## Harmonies

- Complementary: #9a8751
- Analogous: #51879a, #63519a
- Triadic: #9a5163, #639a51
- Split-complementary: #9a6351, #879a51
- Tetradic: #9a5187, #9a8751, #519a63

## Colors that go with #51639a

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 #51639a: softer than #000 and cool enough to feel like part of the same palette. Seen in: Amazon (https://brandsweets.com/colors/brands/amazon-com), Harbour (https://brandsweets.com/palettes/cool#harbour), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #51639a — 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), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com). — https://brandsweets.com/colors/seagreen
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #51639a on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre). — https://brandsweets.com/colors/darkolivegreen
- **Amber** #ffbf00 [pool] — Amber is paired with #51639a in 8 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] — 4 real palettes, including Activision's brand system and Pixar's brand system put Blue beside #51639a, as the accent. Seen in: Activision (https://brandsweets.com/colors/brands/activision-com), Pixar (https://brandsweets.com/colors/brands/pixar-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #51639a: 7 real palettes, including Fintech Trust and Glacier, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), 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 #51639a in 17 real palettes, including McDonald's's brand system and Marvel's brand system, as the supporting colour. Seen in: McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Netflix (https://brandsweets.com/colors/brands/netflix), Ulta Beauty (https://brandsweets.com/colors/brands/ulta-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #51639a: 5 real palettes, including Venmo's brand system and Deep Water, as the supporting colour. Seen in: Venmo (https://brandsweets.com/colors/brands/venmo-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Astro (https://brandsweets.com/colors/brands/astro-build), Calm (https://brandsweets.com/colors/brands/calm-com). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 5.83:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #465686 (7.15:1)
- On black (#000000): 3.6:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #6275ac (4.66:1); AA: background → #e3e3e3 (4.54:1); AAA: text → #8795c0 (7.09:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/51639a-9ca1c4-df754e-221f2d-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: "#51639a" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.