Color

#1503d3

#1503d3
hex#1503d3
rgbrgb(21, 3, 211)
hslhsl(245, 97%, 42%)
oklchoklch(0.398 0.267 266.5)
Closest name: mediumblue (#0000cd)Relative luminance 0.0493

Colors that go with #1503d3

Charcoal, Crimson and Cobalt 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#c2d303

#035ad3 · #7c03d3

#d31503 · #03d315

Split-complementary

Open in tool →

#d37c03 · #5ad303

#d3035a · #c2d303 · #03d37c

Contrast

#1503d3 as textRatioAAAA largeAAAFix
Aaon white
10.58:1passpasspassPasses AAA — no fix needed.
Aaon black
1.99:1failfailfail
  • AA: use #6b5efd as the text (4.64:1)
  • AAA: use #9086fd as the text (7.01:1)
  • AA: or shift the background to #ababab (4.61:1)
  • AAA: or shift the background to #d4d4d4 (7.14:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1503d3 as the background.

Brands using this color

Fonts for this mood

#1503d3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1503d3
live endpoint

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.

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

analyze #1503d3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1503d3-a49cc4-dfa54e-261f2d-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