Color
#138bc3
#138bc3rgb(19, 139, 195)hsl(199, 82%, 42%)oklch(0.604 0.127 236.8)Colors that go with #138bc3
Charcoal, Crimson and Royal 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 #138bc3: softer than #000 and cool enough to feel like part of the same palette.
Crimson #dc143c
split-complementshippedCrimson is a split-complement of #138bc3: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Royal Blue #4169e1
analogousshippedRoyal Blue is #138bc3's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Copper #b87333
complementaryshippedCopper sits directly opposite #138bc3 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Amber #ffbf00
shippedAmber is paired with #138bc3 in 10 real palettes, including Beach Hut and Wired's brand system, as the supporting colour.
Blue #0000ff
shipped10 real palettes, including Readymag's brand system and Qualcomm's brand system put Blue beside #138bc3, as the supporting colour.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #138bc3: 8 real palettes, including Hershey's's brand system and Glacier, as the supporting colour.
Deep Sky Blue #00bfff
shippedDesigners have shipped Deep Sky Blue with #138bc3: 8 real palettes, including Telegram's brand system and Astro's brand system, as the lead colour.
Real palettes that use #138bc3
Tints & shades
Harmonies
Contrast
| #138bc3 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 3.81:1 | fail | pass | fail | |
Aaon black | 5.51:1 | pass | pass | fail |
|
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #138bc3 as the background.
Brands using this color
Fonts for this mood
#138bc3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
Point 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.
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
›analyze #138bc3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/138bc3-9cb3c4-df4e66-1f232d-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