# #581b8d

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

## Values

- Hex: `#581b8d`
- RGB: rgb(88, 27, 141)
- HSL: hsl(272, 68%, 33%)
- OKLCH: oklch(0.385 0.173 303)
- Relative luminance: 0.0478
- Nearest named color: Intergalactic Settlement (#5b1e8b, Δ 0.905) — https://brandsweets.com/colors/intergalactic-settlement
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/581b8d

## Tints & shades

- Tints (toward white): #6b21ab, #7b26c5, #8d36d9, #9b4fde, #ac6de3, #bb87e8, #cca5ee, #dabff3, #ecddf8, #faf6fd
- Shades (toward black): #501881, #481674, #401467, #38115a, #331051, #2b0d45, #230b38, #1b082b, #13061e, #0b0311

## Harmonies

- Complementary: #508d1b
- Analogous: #1f1b8d, #8d1b8a
- Triadic: #8d581b, #1b8d58
- Split-complementary: #8a8d1b, #1b8d1f
- Tetradic: #8d1f1b, #508d1b, #1b8a8d

## Colors that go with #581b8d

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Crimson** #dc143c [pool] — Crimson is paired with #581b8d in 4 real palettes, including Wells Fargo's brand system and Lenovo's brand system, as the lead colour. Seen in: Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Lenovo (https://brandsweets.com/colors/brands/lenovo-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com). — https://brandsweets.com/colors/crimson
- **Royal Blue** #4169e1 [harmony, pool: analogous] — Royal Blue is #581b8d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Discord (https://brandsweets.com/colors/brands/discord), Nokia (https://brandsweets.com/colors/brands/nokia-com). — https://brandsweets.com/colors/royalblue
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #581b8d on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/olive
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #581b8d: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Tomato** #ff6347 [pool] — 3 real palettes, including FedEx's brand system and dbt Labs's brand system put Tomato beside #581b8d, as the supporting colour. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Golden Hour (https://brandsweets.com/palettes/warm#golden-hour). — https://brandsweets.com/colors/tomato
- **Teal** #008080 [harmony, pool: triadic] — Teal completes a triad with #581b8d — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold). — https://brandsweets.com/colors/teal
- **Sea Green** #2e8b57 [harmony: split] — Sea Green is a split-complement of #581b8d: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. — https://brandsweets.com/colors/seagreen
- **Blue Violet** #8a2be2 [pool] — Blue Violet is paired with #581b8d in two real palettes: Taco Bell's brand system and Twitch's brand system, as the supporting colour. Seen in: Taco Bell (https://brandsweets.com/colors/brands/tacobell-com), Twitch (https://brandsweets.com/colors/brands/twitch-tv). — https://brandsweets.com/colors/blueviolet

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

- On white (#ffffff): 10.73:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.96:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #9b4fde (4.57:1); AA: background → #a8a8a8 (4.51:1); AAA: text → #b67ee7 (7.13:1); AAA: background → #d1d1d1 (7.03:1)

## 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/581b8d-b69cc4-c5cb62-2d1f2d-eae9f1?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: "#581b8d" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.