"Likelihood of confusion" is the legal test the USPTO and the courts use to decide whether two marks can coexist. It's a multi-factor analysis (the DuPont factors) weighing how similar the marks are, how related the goods are, how strong the existing mark is, how the two are marketed, and more. No tool decides that test for you; it's a judgment call that lands with an examiner or, ultimately, an attorney.
What this tool does is screen the factors a name-and-register comparison can measure: the similarity of your name to live marks by sound, spelling, and meaning, and whether they sit in a related goods class. It scores that 0–100 against the live USPTO register and shows the evidence. Think of it as a fast, honest first pass on the mark-similarity side of the analysis: a preliminary screening signal, explicitly not a likelihood-of-confusion determination and not legal advice.
What the score covers, and what it doesn't
It covers: similarity of the marks themselves (sound / appearance / meaning) and relatedness of the goods via Nice class, the factors you can compute from a name and the register.
It can't cover: the strength or fame of the other mark, actual marketplace confusion, the sophistication of buyers, bad-faith intent, or how a specific examiner will weigh everything together. Those need human legal judgment. A high score means the measurable factors point to risk worth investigating; a low score means they don't strongly point that way. Neither is a ruling.
Why an honest partial screen still helps
The mark-similarity factors are where most avoidable conflicts hide, and they're the cheapest to check early. Ruling out the obvious sound-alike and meaning-alike collisions before you invest in a name lets a professional clearance search (if you commission one) start from a much stronger position.
Frequently asked questions
Can a tool tell me if there's a likelihood of confusion?
No, and any that claims to is overreaching. The determination is a legal judgment. This screens the name-similarity factors and flags what's worth a closer look.
Should I still see a lawyer?
For a name you're serious about, yes. This front-loads the screening so that step is more focused.
Screen your name now
Check it against millions of live U.S. trademarks by sound, spelling, and meaning. Free, no account.