How to Easily Check Your Thesis for AI Text: Here's How

At German universities, a rough consensus has taken shape by now: generative AI may be used as a tool, for example for research, for feedback, or to refine your phrasing, as long as your work remains your own achievement and you're transparent about how you used AI. Having the AI write your entire paper, on the other hand, counts as academic deception, much like ghostwriting. Many universities have published their own guidelines on this, for example the orientation framework from the University of Hamburg or the guidance from the University of Tübingen. In the end, what's binding is always your own university's examination regulations.

That's exactly why you should know which parts of your work look like AI. There are two reasons for this. First, pure AI text stands out to both examiners and AI detectors. Second, and many people overlook this: AI text can even turn into plagiarism. We'll explain why further down. We'll show you how to recognize AI text, how detection works, how reliable it is, and how to safely check your term paper or thesis before you hand it in.

 

📌 In short:

An AI detector checks your text for patterns that are typical of ChatGPT and the like, and flags passages that were probably written by an AI. It gives you a probability, not proof. So false alarms are possible. For you, that means: check it yourself before submitting, revise suspicious passages, and, when in doubt, be ready to show how you worked.

Want to check it yourself quickly? Easily and without signing up, using the GoThesis AI detector: check your work for AI text.

What is an AI detector and what can it do?

An AI detector is a tool that analyzes your text to determine whether it was written by an artificial intelligence like ChatGPT. Instead of comparing it against sources, the way a plagiarism check does, it looks for linguistic patterns that are typical of machine-generated text and estimates how likely it is that individual passages are AI-generated.

The emphasis on probability is key. An AI detector doesn't prove anything, it works with statistics. Good tools therefore show you not just a percentage but, passage by passage, how suspicious each one is. The GoThesis AI detector, for example, flags text in three levels: possibly, probably, or very probably AI-generated. It recognizes content from the common models like ChatGPT, Gemini, and Copilot.

 

How do you recognize AI text?

Even without a tool, there are telltale signs that you and your examiners can use to spot AI text:

• Too smooth and uniform. AI writes grammatically clean but often strangely average, with little variation in rhythm and hardly any rough edges.
• Clichés and filler sentences. Phrases like “In today's world…,” “It is important to note that…,” or “In conclusion, it can be said that” pile up.
• Surface-level statements. Lots of things that are generally true, but little depth, no examples of your own, no real argument.
• Missing or made-up sources. AI likes to “hallucinate” sources that don't exist at all, or leaves out citations entirely.
• No personal voice. The text sounds interchangeable, as if no one in particular wrote it.

People usually spot AI by gut feeling, detectors by statistics. The most reliable approach combines both.

 

How does AI detection work?

AI detectors take advantage of how language models write in the first place. An AI picks, word by word, the statistically most likely next word every time. This makes its texts very predictable and even. Technically, this is called low perplexity, meaning the text is not very surprising, and low burstiness, meaning the sentences barely vary in length and structure.

People write more irregularly: sometimes a short sentence, then a long, nested one, and an unusual word in between. It's exactly this irregularity that pure AI text often lacks. The detector measures these patterns and derives a probability from them. Because these are only patterns, it can be wrong too. More on that in a moment.

How reliable are AI detectors?

Honestly: good, but not error-free. There are two types of errors you should know about:

• False positives: A text you wrote yourself gets flagged as AI. This happens especially with a very factual, smooth writing style, or if you're not a native speaker and therefore phrase things more uniformly.
• False negatives: An AI text slips through, for instance when it has been heavily rewritten.

So the rule is: an AI detector is a warning sign, not a verdict. Use it to find and revise suspicious passages, not as a free pass and not as proof in either direction. That's exactly why reputable universities should never rely on a detector's result alone.

 

AI text and plagiarism: how AI can turn into plagiarism

Many people think AI text and plagiarism are two completely separate topics. In fact, they're more closely connected than you'd expect, and that's the real reason you should keep an eye on both:

• AI borrows phrasing from its training data, sometimes close to the original wording of existing texts. If you take that over without checking, it can turn into classic plagiarism, even though you never copied anything yourself.
• AI invents sources. It generates authors, titles, or page numbers that don't exist. Such fabricated citations get caught at the latest when someone double-checks them, and count as a serious academic error.
• Passing off AI text as your own work is deception, and if it contains other people's content without a source, it's also plagiarism.

Good to know: a plagiarism check and an AI detector check two different things and don't replace each other.

	Plagiarism check	AI detector
Looks for	text taken from existing sources	machine-generated passages
Question	“Is this from somewhere else?”	“Is this from an AI?”

 

Some university systems like Turnitin have now added AI detection on top, but you can't rely on that. If you really want to be sure, you check your work for both, for example with the GoThesis plagiarism and AI check. You can read how the classic plagiarism check works in our article on the free plagiarism check and in our comparison of plagiarism software.

 

How do universities and professors detect AI text?

Examiners rarely rely on a tool alone. Most often, AI stands out through breaks in style. If your work suddenly sounds much smoother than your previous work or than the way you speak, supervisors get suspicious. Add to that missing or incorrect sources, strikingly generic statements, and a text with no recognizable personal touch.

On top of that, some universities use AI detectors or Turnitin's AI detection and, when in doubt, simply ask about it in the oral defense. Anyone who can explain and defend their own work has a clear advantage here. And that's exactly the heart of the university consensus: AI as a helper is fine, as long as the achievement and the understanding are yours.

Is AI allowed in a term paper or thesis?

As mentioned above, that depends on your university and its specific examination regulations. In practice, though, most rules come down to the same thing:

• Allowed: AI is usually fine as support, that is, for research, ideas, feedback, or improving your language.
• Required at many universities is disclosing your use of AI, for example in a list of tools used or in the declaration of authorship.
• Prohibited is having the whole paper or major parts of it fully generated and passing it off as your own work.

When in doubt: read the examination regulations and ask your supervisor. We show you how to use AI sensibly and within the rules in our article on AI tools for your studies.

 

Check your work for AI text: the GoThesis AI detector

If you want to know before submitting where your work might stand out as AI, it's best to check it with a tool that shows you each suspicious passage individually. That's exactly what the GoThesis AI detector does: you upload your work and can check your work for AI text, right inside the interactive portal. There you'll see which passages are considered AI-generated, flagged in three levels from “possibly” to “very probably.” It recognizes ChatGPT, Gemini, and Copilot.

 

Uploading and the first look inside the portal are free, and you don't need an account. You only provide an email address, which is where the full report is sent. Your document is deleted automatically, never ends up in a public database, and is not shared with universities.

Here's how it works:

1. Upload your document (PDF or Word, up to 15 MB).
2. View the free preview: in the portal, you see how your work is assessed.
3. Unlock the full report once you're convinced, from €6.90 for a term paper and €9.90 for bachelor's and master's theses.

 

The safest approach is to check both. The AI detector and the plagiarism check cover different risks, and as described above, AI text can even turn into plagiarism. At GoThesis you get both from a single portal: if you start with the AI detector, you can add the plagiarism check right afterward. And the other way around, you can add the AI check to the plagiarism check. That way you can also check your work for plagiarism, following the same principle: a free first check, no account, with automatic deletion. You can read how GoThesis performs in practice in our review.

 

Ready for the check?

Upload your work and see within a few minutes which passages count as AI. Free and without signing up: check for AI text now.

 

What to do if your text is wrongly classified as AI

False positives happen, especially with a factual writing style. If a detector or your university wrongly classifies you as AI, one thing helps most of all: being able to prove how you worked. In practical terms, that means:

• Document your writing process: drafts, notes, outlines, and the version history, for example in Word or Google Docs, show that the text grew along with you.
• Back up your research: a clean collection of sources makes clear that you really dug into the topic.
• Revise very smooth passages: your own examples, concrete references, and your personal take lower the risk and make the work better.
• Reach out proactively: anyone who can openly explain how the work came about usually clears up an AI suspicion quickly.