Color Distance Calculator

Measure the perceptual difference between two colors using different algorithms

Calculate the perceptual difference between two colors using the Delta E (CIEDE2000) algorithm. This professional metric indicates how distinguishable two colors are to the human eye.

Algorithm: CIEDE2000 - Industry standard for color difference measurement

Color 1

rgb(255, 0, 0)

Color 2

rgb(255, 51, 51)

Result

ΔE 2000 (CIEDE2000)

6.06

Most accurate

ΔE 76 (CIE76)

18.30

Simpler

Very Noticeable

Very obvious difference. Colors are completely distinct.

Visual Comparison

L*a*b* Breakdown

Shows where the two colors differ: L* = lightness, a* = red/green axis, b* = blue/yellow axis.

L*Lightness
C1: 53.2
C2: 56.0
Δ+2.7
a*Red ↔ Green
C1: 80.1
C2: 73.7
Δ-6.4
b*Blue ↔ Yellow
C1: 67.2
C2: 50.3
Δ-16.9

Interpretation Guide

< 1.0

Imperceptible

1.0 - 2.0

Barely Perceptible

2.0 - 3.5

Perceptible

3.5 - 5.0

Noticeable

> 5.0

Very Noticeable

Export Report

How it works

Color distance measures how different two colors are perceived by the human eye. Unlike calculating Euclidean distance in RGB, Delta E algorithms work in the CIE L*a*b* color space, which better models visual perception.

Delta E (ΔE) — Reference scale

  • ΔE < 1: Imperceptible — Colors look identical to the naked eye
  • ΔE 1-2: Perceptible only by experts with direct comparison
  • ΔE 2-3.5: Perceptible — A subtle difference is noticeable
  • ΔE 3.5-5: Noticeable — Clear and obvious difference
  • ΔE > 5: Very noticeable — Clearly different colors

📊 ΔE76 vs ΔE2000

This tool shows both algorithms:

  • ΔE76 (CIE76): Simpler formula — Euclidean distance in L*a*b*. Fast but inaccurate for blues and saturated colors.
  • ΔE2000 (CIEDE2000): The modern standard. Weights lightness, chroma, and hue based on human perception. Much more accurate.

For most professional uses, always use ΔE2000.

🧪 CIE L*a*b* Color Space

The L*a*b* breakdown shows where two colors differ:

  • L* (Lightness): 0 = black, 100 = white. Large ΔL = brightness difference.
  • a* (Red ↔ Green): Positive values = reddish, negative = greenish.
  • b* (Blue ↔ Yellow): Positive values = yellowish, negative = bluish.

🏭 Industry tolerances

  • Offset printing: ΔE < 2 (ISO 12647 standard)
  • Textile: ΔE < 1.5 (demanding)
  • Automotive: ΔE < 0.5 (extremely strict)
  • Web/digital: ΔE < 3 (acceptable due to monitor variation)
  • Packaging: ΔE < 2 for brand colors

💡 Practical Use Cases

Case 1: Print quality control

Verify that printed color matches the original design.

→ ΔE < 2: Acceptable for most uses
→ ΔE < 1: Premium/exact quality

Case 2: Cross-platform brand consistency

Verify that your web blue matches your native app and corporate PDF.

→ Compare HEX from all platforms
→ Check the L*a*b* breakdown to see if they differ in brightness, hue, or saturation

Case 3: Accessible palette — distinguishable colors

You need chart or dashboard colors to be distinguishable from each other.

→ ΔE > 5 between each pair ensures they are clearly different
→ Especially important for people with color blindness

Case 4: Finding a Pantone alternative

Your brand's Pantone color has no exact HEX equivalent.

→ Compare HEX candidates against the converted Pantone
→ Choose the one with lowest ΔE2000

⚡ Pro tip

The "Export Report" button copies a full summary with both ΔE values, L*a*b* values and per-component differences. Ideal for documenting color decisions in your team.

Frequently Asked Questions

What is color distance used for?
Print quality control, verifying brand consistency across platforms, finding similar colors, validating color reproduction on different devices, and ensuring palette colors are sufficiently distinguishable from each other.
What is the difference between ΔE76 and ΔE2000?
ΔE76 is a simple formula (Euclidean distance in L*a*b*) but doesn't reflect human perception well, especially for blues and saturated colors. ΔE2000 weights lightness, chroma, and hue based on how the eye perceives them, making it much more accurate. Always use ΔE2000 for professional decisions.
What does the L*a*b* breakdown mean?
L* measures lightness (light vs dark), a* measures the red-green axis, and b* measures the blue-yellow axis. If ΔL is large, colors differ in brightness. If Δa is large, they differ in their red/green component. This tells you exactly WHY two colors look different.
What ΔE tolerance should I use?
It depends on context: offset printing ΔE < 2 (ISO 12647), textile ΔE < 1.5, automotive ΔE < 0.5, web/digital ΔE < 3 (due to monitor variation). For web brand consistency, ΔE < 3 is generally acceptable.
Why not use direct RGB distance?
RGB space is not perceptually uniform: a change of 10 units in the red channel is perceived differently than 10 units in blue. CIE L*a*b* models human perception, so ΔE in L*a*b* is a much more reliable measure of perceived difference.
How do I know if two colors are distinct enough for a chart?
For charts and dashboards, ensure each color pair has ΔE > 5. For people with color blindness, also check that differences are concentrated in L* (lightness) and not just in a* (red-green axis), since color blindness affects precisely that axis.