Blue `#0000FF`

Blue (#0000FF) is a dark, vivid blue with an OKLCH hue of 264°, lightness 0.45 and chroma 0.313. It sits on the cool side of the color wheel. In practice it behaves as an accent color: strong in focal moments, dominant over large fields.

Color values

HEX	`#0000FF`
RGB	`rgb(0, 0, 255)`
HSL	`hsl(240, 100%, 50%)`
HSV	`hsv(240, 100%, 100%)`
CMYK	`cmyk(100%, 100%, 0%, 0%)`
CIE Lab	`lab(32.3 79.2 -107.9)`
OKLCH	`oklch(0.452 0.313 264)`

How Blue behaves under real light

Under warm 2700K interior light Blue shifts noticeably: leans toward purple, loses intensity; in north-facing or shaded light it is virtually unchanged. Overall drift across common illuminants is small (max ΔE ≈ 2.9), so it is a lighting-stable choice.

Warm interior (2700K incandescent / warm LED): → #1c14f0 — ΔE 2.9, shifts noticeably: leans toward purple, loses intensity
Neutral LED (4000K task and retail lighting): → #110efb — ΔE 1.1, shifts only faintly, with no single dominant change
Daylight (6500K standard daylight (reference)): → #0000ff — ΔE 0.0, is virtually unchanged
North light / shade (~7500K diffuse blue-sky light): → #0000ff — ΔE 0.0, is virtually unchanged

Contrast & accessibility

Against white it measures 8.59:1 and against black 2.44:1, so white text is the stronger pairing. That pairing passes WCAG AA for body text. Avoid black text on this color entirely.

Palettes built from Blue

Tonal

One color explored: close hues with real lightness and chroma structure, so the palette is the anchor through value rather than a set of colors.

#7ca6ff · #3e77ff · #0000ff · #0000bd · #00006b · #000025

Analogous

The anchor's neighbours on the wheel — everything shares an undertone, so the chord carries color without anything having to be muted to get along.

#0083b1 · #006ab1 · #0000ff · #3d00be · #430086 · #3d0056

Shifted

The mid-gap pairing — sage and mustard, terracotta and olive. A foil rotated 40–65° toward warm or cool: too far to be kin, too near to argue, carried by temperature and a deliberate value offset.

#d889f7 · #cf38ff · #9550af · #0000ff · #0000b7 · #000075

Contrast

One deliberately opposed voice — a single restrained counterpoint across the wheel, or temperature against temperature where the anchor is too muted to carry a loud opposite.

#f7b900 · #6492f5 · #5974ad · #0000ff · #06288f · #031550

Quiet Support

The anchor as the only color in the room. True neutrals or complement-warmed near-neutrals let it stay dominant.

#fff0d3 · #9aaed7 · #796e59 · #0000ff · #293c65 · #0e0600

Bright Accent

This color as a ground rather than a subject — its own restraint held across a narrow value band, carrying one saturated voice from the opposite temperature.

#f7f1e6 · #d1cbbe · #a8a193 · #372e1c · #150c00 · #0000ff

Complementary

The opposite hue on the perceptual wheel, tempered to field strength — warm/cool tension without vibration.

#fff0d3 · #dca400 · #8e6800 · #0000ff · #503900 · #000012

Split-complementary

The complement's two neighbours instead of the complement itself — strong contrast with a lower clash risk.

#fff0d3 · #ff8b2e · #6f7600 · #0000ff · #612d00 · #030200

Triadic

Three hues spaced evenly around the wheel; the anchor leads and the other two are held at supporting strength.

#ffedeb · #ff857f · #008719 · #0000ff · #004c09 · #080000

Tetradic

Two complementary pairs offset by 90° — the richest chord, kept usable by a strict lightness hierarchy.

#ffecf3 · #ff7ab6 · #8e6800 · #0000ff · #00493b · #0e0600

Tints, shades & muted variants

Tints

#1A56FF · #467EFF · #719EFF · #9CBCFF · #C6D9FF

Shades

#0000D8 · #0000B2 · #00008E · #00006B · #00004B

Muted

#0539DB · #1F4AB8 · #355394

Using Blue

Its chroma is high enough to carry accents, calls to action, and focal moments; large fields of it will dominate a composition. In palettes it pairs most predictably with its tonal ramp and analogous neighbors; reserve the complementary hue for small, deliberate contrast.