Color

#2101ef

#2101ef
hex#2101ef
rgbrgb(33, 1, 239)
hslhsl(248, 99%, 47%)
oklchoklch(0.438 0.293 267.7)
Closest name: Burning Ultrablue (#150aec)Relative luminance 0.0658

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#cfef01

#0158ef · #9701ef

#ef2101 · #01ef21

Split-complementary

Open in tool →

#ef9701 · #58ef01

#ef0158 · #cfef01 · #01ef97

Contrast

#2101ef as textRatioAAAA largeAAAFix
Aaon white
9.07:1passpasspassPasses AAA — no fix needed.
Aaon black
2.32:1failfailfail
  • AA: use #725dfe as the text (4.71:1)
  • AAA: use #9585fe as the text (7.06:1)
  • AA: or shift the background to #b8b8b8 (4.57:1)
  • AAA: or shift the background to #e3e3e3 (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #2101ef as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#2101ef reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #2101ef
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #2101ef and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/2101ef-a69cc4-dfac4e-271f2d-e9ecf1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md