Color Difference Calculator

Color difference explained

What is Delta E—and why is it useful?

Delta E, written as ΔE, describes a calculated distance or difference between two colors. In color science, the symbol Δ means change or difference, while E comes from the German word Empfindung, relating to sensation or perception.

Instead of simply asking whether two HEX codes are identical, a Delta E calculation analyzes how their color coordinates differ under a particular mathematical formula.

Smaller scores generally mean a closer color match. Identical colors produce zero difference. As the calculated difference increases, the colors tend to appear less similar, although the exact perceptual relationship depends on the chosen formula and viewing conditions.

This makes Delta E useful for investigating brand-color consistency, interface colors, digital design variations, and many kinds of color-quality comparisons.

ΔE = 0

Identical colors

The two color values are the same under the calculation. Zero is the exact-match baseline for the three formulas in the tool.

Small ΔE

A closer match

A smaller value indicates less calculated difference. Whether someone notices that difference depends on the colors and the viewing conditions.

Large ΔE

A greater difference

Larger values indicate a more substantial calculated difference under the selected formula. This does not by itself establish a tolerance failure.

Three methods of color investigation

CIE76 vs CIE94 vs CIEDE2000: the formulas behind the numbers.

Not all Delta E calculations use the same definition of color distance. Each formula approaches the problem differently, which is why the same two colors can produce different scores.

76

ΔE

CIE 1976 · ΔE*ab

CIE76 — The classic distance

The original CIELAB color difference formula measures straight-line, Euclidean distance between two Lab coordinate points.

It is straightforward and useful for learning color-space distance, but equal numerical differences do not correspond equally well to human perception throughout the entire Lab space.

94

ΔE

CIE 1994 · ΔE94

CIE94 — The weighted approach

CIE94 improves on the simple Lab distance by applying weighting to lightness, chroma, and hue differences.

The formula includes application-specific parameters. UtilityGlen uses the graphic-arts parameter set, rather than the textile variant.

00

ΔE

CIE 2000 · ΔE00

CIEDE2000 — The refined model

CIEDE2000 introduces additional corrections to address known perceptual nonuniformities in CIELAB color differences.

It considers lightness, chroma, and hue interactions using a more sophisticated calculation. It is often preferred when evaluating relatively small perceptual color differences.

The classic CIE76 equation EUCLIDEAN DISTANCE

ΔE*ab = √[(ΔL*)² + (Δa*)² + (Δb*)²]

ΔL*

Difference in lightness

Δa*

Difference along the green–red axis

Δb*

Difference along the blue–yellow axis

CIE94 and CIEDE2000 use more complex expressions. The live calculator computes all three formulas automatically, so you can compare their results without calculating them by hand.

Reading the evidence

How should you interpret a Delta E score?

The essential principle is simple: lower Delta E means less calculated color difference. But deciding whether a difference is acceptable requires context.

The same numerical score may be perceived differently depending on illumination, display calibration, image content, surrounding colors, and the observer. Different Delta E formulas also have different scales.

Exact match Two identical color values produce zero difference.

Very close A small calculated difference may be difficult to notice.

Noticeable Differences may become apparent in comparison.

Distinct The colors generally appear more obviously different.

Strong contrast The pair shows a substantial color separation.

Important: These labels are descriptive, not industry-approved tolerances. There is no universally valid pass/fail Delta E threshold for all applications. Always report the formula and specify your acceptance criteria.

Check your pair's live Delta E scores

Understanding the coordinates

Behind the HEX codes: a closer look at CIELAB.

HEX colors describe red, green, and blue channel values in the sRGB color space. Delta E comparisons need a different representation to investigate perceptual differences.

The UtilityGlen calculator converts your two sRGB colors through XYZ into CIELAB coordinates using a consistent D65 reference white.

In CIELAB, L* describes lightness, a* describes position along a green-to-red opponent axis, and b* describes position along a blue-to-yellow opponent axis.

The calculator displays both colors' coordinates alongside their RGB channels, helping you understand which dimensions contribute to the difference.

Inspect CIELAB values

A* / B* coordinates COLOR SPACE CONCEPT

−a* green +a* red +b* yellow −b* blue

Sample A Sample B L* = separate axis

Conceptual diagram only. Point locations and distance are illustrative, not computed CIELAB coordinates. The real tool displays numerical Lab results.

Your color comparison workflow

How to calculate Delta E between two HEX colors.

No spreadsheets, manual Lab conversions, or complicated equations required. Just follow this process to compare two colors and explore the result.

01

Choose your colors

Enter a three-digit or six-digit HEX code for Color A and Color B, or choose colors using the visual picker.

02

Select a Delta E formula

Choose CIEDE2000, CIE94, or CIE76 for the main result. The calculator also displays all three calculated scores.

03

Inspect the comparison

Review the main score, side-by-side color swatches, CIELAB coordinates, and RGB channel differences.

04

Save or share your findings

Copy the result, download JSON or CSV, or create a shareable link containing the selected colors and formula.

Try a simple experiment.

Enter the same HEX value in both color fields. Every Delta E formula should return zero. Then adjust one color slightly and observe how the scores begin to diverge. It's a useful way to understand why the formula matters.

Try the built-in example comparisons

Beyond the color picker

Where can a Delta E calculator make a real difference?

Color consistency matters in branding, product design, creative production, and software development. Here are six common situations where numerical color comparisons can provide useful information.

Brand Color Consistency

Compare a proposed brand color with a reference HEX code. Quantify how much a digital variation differs rather than relying entirely on visual judgment.

Web & UI Design

Explore differences between interface accents, button variations, backgrounds, and design tokens. Pair Delta E with actual UI previews and contrast tests.

Print Color Education

Understand the formulas used in print color-difference discussions. Real print acceptance testing requires measured color data and standardized conditions, not HEX codes alone.

Photography & Imaging

Investigate changes in selected digital colors after editing, color correction, or processing. Keep color management consistent when comparing image values.

Design System Audits

Compare near-duplicate color tokens and investigate whether existing palette entries are effectively redundant or intentionally distinct.

Color Science Learning

Learn why Euclidean RGB distance and perceptual color difference are different ideas. Experiment with Lab coordinates and the three CIE formulas.

A vital distinction

Delta E is not the same as a WCAG contrast ratio.

Both measurements involve colors, but they answer different questions.

Delta E asks how different two colors are according to a selected color-difference formula.

WCAG contrast ratio evaluates the relative luminance relationship between foreground and background colors for accessibility criteria.

A large Delta E score does not automatically mean text meets WCAG. If you are designing readable text, test the actual foreground/background contrast separately.

ΔE = Color difference WCAG = Text contrast criteria

Color difference

How different are these two colors?

Text contrast

Can people read this?

Foreground and background contrast is a separate accessibility question.

Developer-ready evidence

From color comparison to reusable data.

When you have found a useful comparison, you can keep more than just a screenshot.

The calculator lets you copy the result, download JSON or CSV, or generate a shareable URL.

Exported information can help you document color comparisons, share findings with teammates, or record calculations in project notes and audit reports.

For professional specifications, remember to identify the Delta E formula and measurement or conversion conditions.

View Export Options

delta-e-example.json

// Illustrative data structure
// Values shown are not calculated scores.

{
  "reference": {
    "hex": "#6366F1",
    "space": "sRGB"
  },

  "comparison": {
    "hex": "#8B5CF6",
    "space": "sRGB"
  },

  "difference": {
    "CIE76": null,
    "CIE94": null,
    "CIEDE2000": null
  },

  "note":
    "Calculate with UtilityGlen"
}

This is an educational JSON example, not the tool's exact exported file schema. Use the live calculator to obtain real values and actual JSON/CSV output.

The questions behind the numbers

Color Difference Calculator FAQ

Everything you need to know about Delta E formulas, HEX color comparison, perceptual color difference, CIELAB, tolerance interpretation, and exporting results.

What does Delta E mean in color science?

Delta E (ΔE) describes a calculated difference between two colors using a specified color-difference formula.

Different formulas, such as CIE76, CIE94, and CIEDE2000, use different mathematical approaches. A Delta E score should always be reported with its formula.

How do I calculate Delta E between two HEX colors?

Enter your two HEX values in UtilityGlen's Color Difference Calculator. The tool converts the sRGB colors into CIELAB coordinates and calculates ΔE76, ΔE94, and ΔE2000.

You can choose which formula appears as the primary score while viewing the other results alongside it.

What is CIEDE2000 or Delta E 2000?

CIEDE2000, commonly written as ΔE00, is a color-difference formula designed to better model several nonuniformities in perceived color difference.

It applies adjustments involving lightness, chroma, hue, and interactions between those dimensions. It is often preferred over simple CIE76 distance for many small-color-difference comparisons.

What is the difference between Delta E 76 and Delta E 2000?

CIE76 measures straight-line distance in CIELAB space. CIEDE2000 introduces additional corrections intended to better correspond with human color-difference perception.

Because the two formulas measure color difference differently, their numerical values for the same pair are not directly interchangeable.

What is Delta E 94 used for?

CIE94 is a weighted color-difference formula that accounts for differences in lightness, chroma, and hue.

It includes different parameter sets for applications such as graphic arts and textiles. UtilityGlen's calculator uses the graphic-arts parameter set.

What is a good Delta E 2000 value?

Lower ΔE00 values indicate closer color matching. However, there is no single universally correct pass/fail threshold.

Acceptable differences depend on the application, material, viewing conditions, measurement process, and the tolerance specified for the project.

The calculator's informal score descriptions are orientation aids, not professional certification limits.

Is a Delta E value of zero a perfect match?

A Delta E score of zero indicates that the two color coordinates are identical under the selected calculation.

For identical HEX values interpreted in the same sRGB color space, the three formulas in UtilityGlen's calculator return zero.

Can two colors look identical but have different HEX codes?

Yes. Two different HEX values can produce colors that appear very similar to an observer, especially under particular viewing conditions.

Delta E provides a numerical way to investigate their calculated difference. Perceived similarity still depends on the observer, display, and visual context.

What is CIELAB, and why does Delta E use it?

CIELAB is a color space defined using three coordinates: L* for lightness, a* for the green–red opponent direction, and b* for the blue–yellow opponent direction.

It was designed to provide a more perceptually meaningful representation than raw RGB channel values, although CIELAB is not perfectly uniform.

CIE76, CIE94, and CIEDE2000 work with colors expressed in CIELAB.

Can I compare RGB colors using Delta E?

Yes. RGB colors can be converted into a suitable colorimetric space before calculating Delta E.

UtilityGlen accepts sRGB HEX input and displays the corresponding RGB and CIELAB values. Its conversion uses a consistent reference white for both colors.

Is Delta E the same as RGB color distance?

No. A raw RGB channel distance measures separation between red, green, and blue channel values. RGB distances are not perceptually uniform.

Delta E formulas aim to represent color differences more meaningfully using CIELAB coordinates and, in newer formulas, perceptual corrections.

The calculator displays both per-channel RGB differences and the Delta E scores.

Can Delta E tell me whether text is accessible?

No. Delta E measures color difference according to a selected formula. It does not directly determine WCAG text-contrast compliance.

To evaluate foreground and background text colors against WCAG 2.x contrast criteria, use a dedicated contrast-ratio checker.

Can I use this calculator for professional print color tolerances?

The calculator is useful for learning the formulas and comparing digital sRGB color values.

Professional print quality control usually requires measured color data, defined illuminants, measurement geometry, calibrated instruments, and agreed tolerance criteria.

HEX-only comparisons are not a replacement for instrument-based print evaluation.

Can I export or share my Delta E comparison?

Yes. UtilityGlen lets you copy comparison results, download JSON or CSV files, and generate a shareable comparison URL.

The share link encodes the selected HEX pair and formula in the URL, making it easier to revisit the same comparison.

The Color Difference Calculator is free to use in your browser, with no account required.

Two colors. One question.How different do they really look?

Compare two colors

Perceptual difference report

Direct color comparison

The colors in CIELAB

Color A

Color B

Visual color-difference explorer

Try these color comparison examples

Developer-ready comparison data

Two colors. One question. How different?