Circuit
Open in tool →Violet plus cyan is the current AI-product signal — pair it with pure black type to keep it from going candy.
Color
#18b5dc
#18b5dc
hex
#18b5dcrgb
rgb(24, 181, 220)hsl
hsl(192, 80%, 48%)oklch
oklch(0.717 0.128 221.2)Closest name: Aquarius (#2db0ce)Relative luminance 0.3841
Colors that go with #18b5dc
Charcoal, Denim and Midnight Blue 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 #18b5dc: softer than #000 and cool enough to feel like part of the same palette.
Denim #1560bd
shippedDesigners have shipped Denim with #18b5dc: 6 real palettes, including Coca-Cola's brand system and Gopro's brand system, as the accent.
Midnight Blue #191970
shipped8 real palettes, including Confluent's brand system and SoFi's brand system put Midnight Blue beside #18b5dc, as the lead colour.
Royal Blue #4169e1
shippedRoyal Blue is paired with #18b5dc in 8 real palettes, including Confluent's brand system and Elastic's brand system, as the supporting colour.
Taupe #483c32
shippedTaupe is paired with #18b5dc in 9 real palettes, including Cursor's brand system and Astro's brand system, as the text colour against it.
Coral #ff7f50
complementaryCoral sits directly opposite #18b5dc on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Peru #cd853f
split-complementshippedPeru is a split-complement of #18b5dc: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Amber #ffbf00
shippedAmber is paired with #18b5dc in 3 real palettes, including Blueprint and Salesforce's brand system, as the accent.
Real palettes that use #18b5dc
Tints & shades
Harmonies
Contrast
| #18b5dc as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.42:1 | fail | fail | fail | |
Aaon black | 8.68:1 | 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 #18b5dc as the background.
Brands using this color
Palettes built around it
Deep Water
Open in tool →Cyan and mid-blue on abyss navy with a foam highlight — the ocean at depth; the darker the surface, the brighter the water.
Lagoon
Open in tool →Turquoise and teal with a sand-yellow on white — shallow tropical water; the deep teal text is the reef.
Fonts for this mood
#18b5dc reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #18b5dc
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 #18b5dc and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/18b5dc-a2b5be-df4e77-1f242d-e9f1ef?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