COPYRIGHT FOR CRAFTERS — POST 3

The “Change It 10% and You’re Fine” Myth

Why there’s no magic number — and what actually matters

By Penny  |  pennysdream.com  |  April 23, 2026  |  7 min read

If you’ve spent any time in crafting groups online — Facebook, Reddit, anywhere — you’ve heard some version of this: “Just change it 10% and you’re fine.”

Or 20%. Or 30%. Pick a number. It floats around like a rule everybody knows but nobody can quite source. Someone says it in the comments, someone else repeats it in a different group, and before long it feels like established fact.

Here’s the thing: this rule does not exist. Not in copyright law. Not in any court ruling. Not anywhere. It’s one of those bits of crafting folklore that sounds reasonable enough that nobody questions it. But it’s not true, and relying on it can get you into real trouble.

So let’s talk about where it came from, what courts actually look at, and what this means for those of us making and selling handmade things.

(If you’re just joining the series, the previous post was “I Bought the Die — Can I Sell What I Make With It?” — worth a read if you missed it.)

So Where Did This “Rule” Come From?

Honestly? Nobody knows exactly. My best guess — and what several intellectual property attorneys have written about — is that it grew out of a misunderstanding of how courts actually evaluate copyright cases.

When someone gets accused of copying, courts don’t pull out a calculator and measure what percentage was changed. They use a concept called “substantial similarity.” That sounds like legal jargon, but the idea behind it is surprisingly simple: would an ordinary person, looking at both works, recognize that one came from the other?

If the answer is yes, you’ve got a problem — no matter how many small changes you made. There’s no threshold. No percentage. No safe number. Somewhere along the way, people took the idea of “how much is too similar” and turned it into a number, probably because numbers feel comforting. But the law doesn’t work that way.

What “Substantial Similarity” Actually Means

Let me explain this the way I wish someone had explained it to me when I first started looking into it.

Courts don’t get out a ruler. They don’t count how many elements you swapped. What they look at is the overall impression — sometimes called the “total concept and feel.” If your version and the original give off the same vibe, use a similar arrangement, similar color choices, similar layout — a few swapped elements aren’t going to save you.

Here’s the test I use in my own head, and it’s basically what courts do too:

 

The Friend Test If you showed both versions to a friend — someone who doesn’t craft and has no stake in the outcome — and they said “those look like the same thing,” that’s substantial similarity. It doesn’t matter that you can see the differences. What matters is the overall impression on a regular person.

 

This is why the percentage thing falls apart. You could change 50% of a design, and if the overall feel is still recognizably the same, it’s still a problem. Or you could change 5% of something in a way that makes it genuinely your own. The math doesn’t matter. The impression does.

What “Inspired By” Actually Looks Like

There’s a real, meaningful difference between being inspired by someone’s work and copying it with tweaks. But I think a lot of us blur that line without realizing it, so it’s worth being specific.

Inspiration means you saw something that sparked an idea — a color combination, a mood, a technique, a general concept — and then you went off and created something new from that spark. The result looks like your work. It reflects your style, your choices, your creative instincts. Someone looking at it wouldn’t point to the original and say “oh, that’s based on so-and-so’s design.”

Here’s a good test I’ve started using:

 

The Spark Test If you removed the original from the equation entirely — if you’d never seen it — would your version still make sense as its own thing? Would it still exist? If yes, that’s inspiration. If your version only exists because the original exists, that’s copying with extra steps.

 

We all absorb influences. That’s normal and healthy and it’s how creative people grow. The key is that the influence gets filtered through you before it comes out the other side.

What “Copied With Changes” Looks Like

This is the uncomfortable part, and I’m including myself in this conversation because I think most of us have been closer to this line than we’d like to admit.

You found a card design you loved. You changed the colors. Swapped one element — maybe a flower for a butterfly. Moved something from the left side to the right. Changed the font. And now it’s … still recognizably that card.

That’s not transformation. That’s modification. And modification doesn’t make it yours.

I know that’s not what anyone wants to hear. But the number of changes genuinely does not matter if the result is recognizably derived from the original. If someone who’d seen the original would look at yours and think “oh, that’s a version of that design,” you’re in tricky territory — especially if you’re selling it.

Gray Areas Crafters Actually Run Into

These aren’t hypotheticals. These are situations I’ve seen come up over and over in crafting communities, and they’re worth thinking through honestly.

Recreating a popular layout from Pinterest with different paper. You found a card layout you loved — the arrangement, the layering, the placement of every element. You used different patterned paper, but the design itself? Identical. This is closer to copying than most people realize, because the arrangement is the creative work, not just the materials.

Making “your version” of a trending sticker design style. When a particular style is everywhere — a certain illustration vibe, a specific lettering approach combined with specific imagery — and you make something that fits right into that trend, the question is whether you’re drawing from a general style (which can’t be copyrighted) or from a specific creator’s specific work (which can). There’s a difference, and it’s worth being honest with yourself about which one you’re doing.

Using a die cut in the exact same arrangement as the company’s product photo. You bought the die, and yes, you can use it. But if your finished piece is a near-replica of the sample layout from the manufacturer’s marketing, that sample layout may have its own copyright protection. The die is a tool. The specific arrangement in their photo is a design choice someone made.

Copying a font pairing, layout, and color scheme from someone’s Etsy listing. Any one of those elements alone? Probably fine. But when you take the whole combination — the specific fonts paired together, arranged in the same layout, with the same palette — you’re not borrowing an idea anymore. You’re borrowing a design.

None of these make someone a bad person. Most crafters stumble into these situations without even thinking about it. But that’s exactly why it’s worth thinking about.

So What Can You Actually Do?

The good news is that protecting yourself here isn’t complicated. It just takes a little bit of intentionality.

Study what you like about a design, then close it. Seriously — close the tab, put down the magazine, scroll past it. Then go create from memory and from your own sensibility. What you produce will naturally be different because it’s filtered through you. The things you remember will be the broad strokes — the feeling, the general idea — and that’s exactly where inspiration lives.

If you can still see the original while you’re working, you’re probably too close. This is my personal rule, and it’s served me well. If the reference image is open on my phone while I’m crafting, I’m not being inspired by it — I’m using it as a blueprint. There’s a difference.

Focus on developing your own style. This is your best protection and your best brand. The crafters who build a real following aren’t the ones who make perfect copies of trending designs — they’re the ones whose work is recognizably theirs. That takes time, and it takes making a lot of things, but it’s the most rewarding path anyway.

When in doubt, ask yourself one question: “Would the original creator recognize their work in mine?” If the answer is yes — or even “maybe” — it’s worth going back to the drawing board. Literally.

The Bottom Line

The 10% rule is a myth. There is no magic number. The real question is whether your work stands on its own or whether it leans on someone else’s. Courts don’t measure percentages. They look at the overall impression. And honestly, so does everyone else.

The good news? If you’re making original work — and most crafters genuinely are — you’re already on the right side of this. The people who need to worry are the ones who are deliberately replicating other people’s designs and telling themselves the changes are enough. For the rest of us, just being aware of this stuff goes a long way.

Next time, we’re tackling another big one: fair use. It’s probably the most misunderstood concept in all of copyright law, and crafters throw it around constantly. Spoiler: it almost certainly doesn’t mean what you think it means.

 

Disclaimer: I’m a crafter, not a lawyer. Everything in this post comes from my own research and curiosity — not legal advice. If real money or a real dispute is on the line, talk to an actual attorney.

 

Where I Looked This Up:

• U.S. Copyright Office — Copyright Basics: https://www.copyright.gov/what-is-copyright/

• Gottlieb, Rackman & Reisman, P.C. — “Copyright and the Myth of the Ten Percent Rule”

• Copyrighted.com — “How Much Do You Need to Change to Avoid Copyright Infringement?”

• This post was written with the help of AI-assisted research and drafting, and reviewed by an actual human crafter (that’s me).

 

Next up →: Fair Use — It Doesn’t Mean What You Think It Means