What is the hex code for Dark Blue?

Dark Blue is #00008b. In CSS the keyword darkblue, the hex #00008b, rgb(0, 0, 139) and hsl(240, 100%, 27%) all paint the same color.

What is the opposite of Dark Blue on the color wheel?

The opposite (complementary) color is #8b8b00, the same saturation and lightness rotated 180° around the HSL wheel. Complementary pairs give the strongest contrast, which is why the complement should be used sparingly rather than at equal weight.

Can I use Dark Blue for text?

Dark Blue as text on white has a contrast ratio of 15.3:1, which passes WCAG AA for body text (4.5:1). On black it is 1.37:1, which fails for body text. It works as a text color on light surfaces.

CSS color names · Blues

Dark Blue color: hex #00008b, RGB and HSL

Dark Blue is the CSS keyword darkblue, hex #00008b, rgb(0, 0, 139), hsl(240, 100%, 27%). It is a dark, fully saturated blue in the blues family. Below: the colors that go with it, its tints and shades, how it reads as text, and a complete interface palette built from it.

CSS name: darkblue
Hex: #00008b
RGB: rgb(0, 0, 139)
HSL: hsl(240, 100%, 27%)
On white: 15.3:1 — passes AA for body text
On black: 1.37:1 — fails AA; use as a fill, not text

.example {
  color: darkblue;          /* keyword */
  color: #00008b;          /* hex */
  color: rgb(0, 0, 139); /* rgb */
  color: hsl(240, 100%, 27%); /* hsl */
}

What colors go with dark blue

Each match keeps dark blue's saturation and lightness and rotates only the hue, so the relationship is the wheel's and nothing else. Any of these can be an accent beside dark blue as the primary; the harmony guides explain which rule suits which interface.

Complementary

The opposite hue, 180° away — the strongest contrast, best kept to one accent per screen.

#8b8b00

Split-complementary

The two neighbors of the complement, at 150° and 210° — most of the contrast with less tension, and two accents instead of one.

#8b4600

#468b00

Triadic

Two hues at 120° and 240° — three evenly spaced signals, the scheme charts and category colors want.

#8b0000 · darkred

#008b00

Analogous

The neighbors at −30° and +30° — calm and cohesive, with emphasis coming from weight and size rather than hue.

#00468b

#46008b

Tints and shades of dark blue

Tints add lightness toward white; shades remove it toward black. The hue and saturation stay fixed, so every step still reads as dark blue — these are the hover, pressed, disabled and surface variants a single brand color needs.

Tints (lighter)

#0000c9

#0808ff

#4545ff

#8383ff

#c1c1ff

Shades (darker)

#000074

#00005d

#000045

#00002e

#000017

A UI color palette built from dark blue

The eight semantic roles an interface actually uses, derived from dark blue as the primary with the split-complementary rule: secondary and accent rotate around the wheel, and the five neutrals take the hue at lightness steps tuned for light and dark mode. This is the same derivation the palette generator runs — open it there to change the rule, drag the anchors, or export the set as CSS variables.

Light mode

primary: #00008b
secondary: #8b4600
accent: #468b00
background: #fcfcfd
surface: #f3f3f7
text: #111122
muted: #56568f
border: #dfdfec

Dark mode

primary: #1a1aff
secondary: #ff8c1a
accent: #8cff1a
background: #0e0e1b
surface: #151528
text: #f3f3f6
muted: #9494b8
border: #272749

Open dark blue in the palette generator

Using dark blue in an interface

Blue is the default interface color for a reason: it sits comfortably behind content, it has a wide usable lightness range for hover and pressed states, and its complement (orange) leaves red and green free for status. Most of the good primaries in this set are here. Whichever role dark blue takes, define it once as a token rather than repeating the keyword: the semantic palette guide covers the eight roles, and the guides to complementary, triadic and the other color schemes explain how to weight the matches above.

What is the hex code for Dark Blue?: Dark Blue is #00008b. In CSS the keyword darkblue, the hex #00008b, rgb(0, 0, 139) and hsl(240, 100%, 27%) all paint the same color.
What colors go with Dark Blue?: Its complement is #8b8b00, the split-complementary pair is #8b4600 and #468b00, the triadic partners are #8b0000 and #008b00, and the analogous neighbors are #00468b and #46008b. In an interface, use Dark Blue for most colored elements and one of these for a single accent, at roughly an 80/20 split.
What is the opposite of Dark Blue on the color wheel?: The opposite (complementary) color is #8b8b00, the same saturation and lightness rotated 180° around the HSL wheel. Complementary pairs give the strongest contrast, which is why the complement should be used sparingly rather than at equal weight.
Can I use Dark Blue for text?: Dark Blue as text on white has a contrast ratio of 15.3:1, which passes WCAG AA for body text (4.5:1). On black it is 1.37:1, which fails for body text. It works as a text color on light surfaces.