# #399fdb

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

## Values

- Hex: `#399fdb`
- RGB: rgb(57, 159, 219)
- HSL: hsl(202, 69%, 54%)
- OKLCH: oklch(0.671 0.128 239)
- Relative luminance: 0.3078
- Nearest named color: Blue Burst (#309cd0, Δ 1.874) — https://brandsweets.com/colors/blue-burst
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/399fdb

## Tints & shades

- Tints (toward white): #4aa8de, #60b2e2, #71bae5, #86c5e9, #98cdec, #a9d5ef, #bee0f3, #d0e8f6, #e5f3fa, #f6fbfd
- Shades (toward black): #2794d3, #2385be, #1f76a8, #1b6793, #17587d, #134867, #0f3952, #0b2a3c, #071b27, #030c11

## Harmonies

- Complementary: #db7439
- Analogous: #39dbc5, #394edb
- Triadic: #db399f, #9fdb39
- Split-complementary: #db394e, #dbc539
- Tetradic: #c539db, #db7439, #4edb39

## Colors that go with #399fdb

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 #399fdb: softer than #000 and cool enough to feel like part of the same palette. Seen in: Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Lido (https://brandsweets.com/palettes/vivid#lido), Blizzard (https://brandsweets.com/colors/brands/blizzard-com), Lagoon (https://brandsweets.com/palettes/vivid#lagoon). — https://brandsweets.com/colors/charcoal
- **Tomato** #ff6347 [harmony, pool: split] — Tomato is a split-complement of #399fdb: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Lido (https://brandsweets.com/palettes/vivid#lido), Substack (https://brandsweets.com/colors/brands/substack-com), Replit (https://brandsweets.com/colors/brands/replit), Hermès (https://brandsweets.com/colors/brands/hermes-com). — https://brandsweets.com/colors/tomato
- **Bronze** #cd7f32 [harmony, pool: complementary] — Bronze sits directly opposite #399fdb on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Opensea (https://brandsweets.com/colors/brands/opensea-io). — https://brandsweets.com/colors/bronze
- **Amber** #ffbf00 [pool] — Amber is paired with #399fdb in 9 real palettes, including Salesforce's brand system and NBA's brand system, as the accent. Seen in: Salesforce (https://brandsweets.com/colors/brands/salesforce-com), NBA (https://brandsweets.com/colors/brands/nba-com), Heatwave (https://brandsweets.com/palettes/warm#heatwave), Blueprint (https://brandsweets.com/palettes/technical#blueprint). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 5 real palettes, including Unity's brand system and Qualcomm's brand system put Blue beside #399fdb, as the supporting colour. Seen in: Unity (https://brandsweets.com/colors/brands/unity-com), Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Warp (https://brandsweets.com/colors/brands/warp-dev). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #399fdb in 4 real palettes, including Riot Games's brand system and JBL's brand system, as the supporting colour. Seen in: Riot Games (https://brandsweets.com/colors/brands/riotgames-com), JBL (https://brandsweets.com/colors/brands/jbl-com), NASCAR (https://brandsweets.com/colors/brands/nascar-com), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/crimson
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #399fdb in 4 real palettes, including Elastic's brand system and Learning App, as the lead colour. Seen in: Elastic (https://brandsweets.com/colors/brands/elastic-co), Learning App (https://brandsweets.com/palettes/playful#learning-app), Ahrefs (https://brandsweets.com/colors/brands/ahrefs-com), Playground (https://brandsweets.com/palettes/bold#playground). — https://brandsweets.com/colors/darkorange
- **Denim** #1560bd [pool] — Designers have shipped Denim with #399fdb: 10 real palettes, including Gopro's brand system and Coca-Cola's brand system, as the lead colour. Seen in: Gopro (https://brandsweets.com/colors/brands/gopro-com), Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Apple (https://brandsweets.com/colors/brands/apple-com), Venmo (https://brandsweets.com/colors/brands/venmo-com). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 2.93:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #207cb1 (4.59:1); AA: background → #2e2e2e (4.63:1); AAA: text → #195e86 (7.03:1); AAA: background → #030303 (7.03:1)
- On black (#000000): 7.16:1 — AA pass, AA-large pass, AAA pass

## 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/399fdb-9cb1c4-df4e5f-1f222d-e9f1f0?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: "#399fdb" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.