Learning App
Open in tool →Green, blue and orange at full saturation: the gamified-learning look, where every color is a reward.
Color
#39a9ef
#39a9ef
hex
#39a9efrgb
rgb(57, 169, 239)hsl
hsl(203, 85%, 58%)oklch
oklch(0.704 0.142 241)Closest name: Cerulean (#55aaee)Relative luminance 0.3548
Colors that go with #39a9ef
Charcoal, Medium Sea Green and Amber lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #39a9ef: softer than #000 and cool enough to feel like part of the same palette.
Medium Sea Green #3cb371
triadicshippedMedium Sea Green completes a triad with #39a9ef — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Amber #ffbf00
shippedAmber is paired with #39a9ef in 6 real palettes, including Salesforce's brand system and NBA's brand system, as the accent.
Blue #0000ff
shipped5 real palettes, including Warp's brand system and Unity's brand system put Blue beside #39a9ef, as the supporting colour.
Dark Orange #ff8c00
shippedDark Orange shows up next to #39a9ef in 5 real palettes, including Learning App and Elastic's brand system, as the accent.
Denim #1560bd
shippedDesigners have shipped Denim with #39a9ef: 6 real palettes, including Coca-Cola's brand system and Apple's brand system, as the accent.
Midnight Blue #191970
shipped7 real palettes, including Kraken's brand system and Blue Mono put Midnight Blue beside #39a9ef, as the lead colour.
Orange Red #ff4500
shippedOrange Red is paired with #39a9ef in 7 real palettes, including Cursor's brand system and Figma's brand system, as the lead colour.
Real palettes that use #39a9ef
Tints & shades
Harmonies
Contrast
| #39a9ef as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.59:1 | fail | fail | fail | |
Aaon black | 8.1:1 | pass | pass | pass | Passes AAA — no fix needed. |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #39a9ef as the background.
Brands using this color
Palettes built around it
Fonts for this mood
#39a9ef reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #39a9ef
live endpointPoint any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #39a9ef and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/39a9ef-9cb0c4-df4e5d-1f222d-e9f1f0?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md