If you’ve ever ordered a new vinyl banner or a set of school signs and thought, “Hmm, this blue looks just a little different than last time,” you’ve probably run into something called Delta E (ΔE).
ΔE is the fancy way of measuring how close (or how far) two colors are from each other. It’s basically a score that says, “Here’s how different these colors will look to the human eye.”
Every color can be mapped into a 3D model called the Lab color space. This system breaks color into:
L* – how light or dark it is
a* – whether it leans green or red
b* – whether it leans blue or yellow
ΔE is calculated by comparing two colors’ positions in that space, like measuring the distance between two points on a map. The bigger the number, the bigger the difference.
Here’s what a ΔE score usually means in real life:
0 – 1 ΔE → No visible difference.
1 – 2 ΔE → Barely noticeable, and only noticeable, if you hold two samples side by side.
2 – 3 ΔE → Slightly different. A trained eye might pick it up, but most people won’t notice unless they’re comparing closely.
3 – 4 ΔE → Noticeable difference. Side by side, you’ll see the shift in tone or shade.
So when we talk about 1–4 ΔE, we’re really talking about “basically identical” to “hey, that’s close, but a little off.”
Let’s put this into context. Imagine your school’s primary color is a deep royal blue. You’re printing different items for an upcoming pep rally.
1 ΔE Difference – Your vinyl banner and your rigid sign are practically identical. If you put them right next to each other in perfect lighting, you might see a tiny difference, but no one else will notice.
2 ΔE Difference – Still very close. A trained designer or printer might say, “Yeah, the banner is just a hair lighter.” But students, parents, and fans will see them as the same school blue.
3 ΔE Difference – This is where the average person could pick up the difference if both items are side by side. Your rigid sign might lean slightly more purple, while the banner is more true-blue. Still acceptable for most uses, but noticeable in certain lighting.
4 ΔE Difference – Now you’ll see it. The vinyl banner might look like one shade of blue and the rigid sign a touch lighter or more saturated. Not a dealbreaker, but if your school branding is super strict, you might flag this as “off.”
When you’re ordering gear, signage, or promotional items, a 1–4 ΔE variance is typically considered in tolerance. That means the colors are close enough to look consistent, even across different printers, materials, or finishes.
It’s the balance between perfection (which is nearly impossible in the real world) and practicality (making sure your school colors still look unified at the pep rally).
Next time you see a slight difference in your school’s colors between your custom printed products, it doesn’t necessarily mean something went wrong. If it’s within 1–4 ΔE, it’s still on-brand and within the normal production standard.