Color Guide

How colors are measured

CIELAB is an easy way of giving every color a precise location in space. Color names are fuzzy — your "rose" and mine might differ — but CIELAB fixes that by plotting each color as a single point in a 3D space built to match how the human eye actually sees. Three numbers pin a color down exactly. Think of it as a color's address.

L* — Lightness

How light or dark the color is, from 0 (black) to 100 (white).

a* — Green → Red

How far the color leans toward green (negative) or red (positive).

b* — Blue → Yellow

How far the color leans toward blue (negative) or yellow (positive).

From those three numbers, color metrics can be derived

Once a color is just three numbers, comparing and describing it becomes simple arithmetic. Each idea in this guide is just a different question asked of those same coordinates:

ΔE — how different two colors are
Undertone — which direction it leans
Depth — how light or dark it is

ΔE: The distance between two colors

If every color is a point in CIELAB space, then the difference between two colors is just the distance between their two points. That distance is ΔE (Delta E), one number for how different two colors look to the human eye. The smaller the number, the more similar the colors. It's the industry standard for color accuracy in cosmetics, printing, and design.

ΔE = √(ΔL*² + Δa*² + Δb*²)

Straight from Pythagoras: ΔE is the straight-line distance between two points in CIELAB space: the differences in L*, a*, and b*, squared, summed, and rooted. Same math as measuring the distance between two pins on a map, just in three dimensions.

The ΔE scale, in plain English

How noticeable is the color difference at each level?

≤ 1ΔE

Imperceptible

The difference cannot be seen by the human eye, even side by side.

Exact match

1–3ΔE

Just noticeable

Trained eyes can detect the difference. Most consumers cannot.

Excellent match

3–6ΔE

Noticeable difference

Most people can see a difference. Still in the same color family.

Good match

6–12ΔE

Clearly different

The difference is obvious at a glance. Related shade, different depth or tone.

Approximate match

> 12ΔE

Different colors

These are distinct shades. Useful as a reference point, not a substitute.

Different shade

How ΔE is used in this tool

Each lipstick in the database has been color-profiled in CIELAB color space using computer vision. When you select a color on the wheel, the ΔE distance from that color to every product in the database is computed and the closest matches are surfaced, ranked from most to least similar.

Undertone: How a color leans

Undertone describes which direction a color leans, independent of how light or dark it is. Colors within the same family can be cool, neutral, or warm.

Cool red

Leans toward blue or pink. Berries, fuchsias, blue‑based reds.

Neutral red

Balanced, neither blue‑ nor orange‑leaning. True reds and balanced rose.

Warm red

Leans toward orange or yellow. Bricks, corals, terracotta reds.

The hue angle on the a*–b* plane — the direction the color points — determines undertone. Hues under ~12° are cool, 12–28° neutral, above 28° warm.

Depth: How light or dark

Depth describes how light or dark a shade appears.

Light

Soft and quiet on the lip. Pales, sheers, washes of color.

Medium

Pigmented but not heavy. The everyday range, most reds and pinks live here.

Deep

Bold and saturated. Vampy, plum, oxblood, deep berry.

Depth is read directly from L* (lightness): under 32 is deep, 32–55 is medium, above 55 is light.