#0000FF: pure blue color codes, contrast and shades

By TechCompare · Updated November 2026 · How we check

#0000FF is rgb(0, 0, 255), the CSS color blue and the blue primary of sRGB. It's a dark color: white text scores 8.59:1, black only 2.44:1.

#0000FF

Color Codes

HEX#0000FF
RGBrgb(0, 0, 255)
HSLhsl(240, 100%, 50%)
OKLCHoklch(45.2% 0.3132 264.05)

Text on #0000FF

White Text

The quick brown fox jumps over the lazy dog.

8.59:1APCA Lc -90.7

AA Normal (4.5:1)Pass
AA Large (3:1)Pass
AAA Normal (7:1)Pass
AAA Large (4.5:1)Pass

Check White Text in Contrast Checker

Black Text

The quick brown fox jumps over the lazy dog.

2.44:1APCA Lc 18.2

AA Normal (4.5:1)Fail
AA Large (3:1)Fail
AAA Normal (7:1)Fail
AAA Large (4.5:1)Fail

Check Black Text in Contrast Checker

WCAG 2 ratios are the same whichever color is the text, so they also hold for #0000FF text on a white or black page. APCA is a newer method that isn't part of any WCAG standard, and a minus sign means light text on dark.

#0000FF in the Color Picker. Tweak it with HSL or OKLCH sliders, or compare it with a second color.

Edit in the full tool

#0000FF turns the blue channel all the way up and leaves red and green off. Even at full strength it's the darkest of the three primaries, at an OKLCH lightness of 45.2%, against 62.8% for pure red and 86.64% for pure green. Your eyes are least sensitive to blue, so it adds the least brightness. The cards above give its codes and test white and black text on it. Below are 4 lighter and 4 darker shades.

Shades

Same hue and chroma in OKLCH, with even steps of lightness. Open any shade in the Color Picker.

Nearest Named Colors

CSS Name
blue
#0000FF
ExactΔE OK 0.000
Tailwind 4
blue-700
oklch(48.8% 0.243 264.376)
Not CloseΔE OK 0.079
Tailwind 3
blue-700
#1D4ED8
Not CloseΔE OK 0.103

About #0000FF

The classic blue link isn't quite #0000FF. The HTML spec's default link color is #0000EE, a touch darker, and visited links turn #551A8B. Both pass AAA on a white page, at 9.40:1 and 11.01:1.

The trouble is dark backgrounds. Blue text on white scores 8.59:1, but blue text on black gets only 2.44:1 and fails at every size. For links in a dark theme, go two steps up the shade scale: #6A9DFF scores 7.88:1 against black.

No Tailwind color matches it. The nearest in Tailwind 4, blue-700, sits 0.079 away in OKLab, a softer blue.

Verdict

Use #0000FF for links and buttons on light backgrounds, with white labels. Keep it away from dark backgrounds as text.

For a lighter blue that still takes white text, #2866FF is the limit, at 4.74:1. The darker steps all keep white text past AAA. Click a shade to open it in the Color Picker.