Artificial intelligence (AI) is with us now, so there’s no turning back. But how do you know if what you read online, or even offline, is human or AI-generated?
On top of that, even if you write every word of a text yourself, could your writing be flagged as AI text?
Problems associated with determining how a text was written have been an issue for students, educators, and creative writers alike.
However, while not perfect, free online tools can help in sorting automated text from human-written text.
Using free detector tools to help you
If you want to check if a piece of writing is AI-generated or human text, online AI detectors are the quickest way to do it.
However, be warned that they can be unreliable, and are certainly not anywhere near 100% proof of how a text was written.
The best approach is to use a few tools to check, and then you can see if the conclusions are similar.
Before I publish anything, I usually check with two or three of these tools. Most of the time, I get a 100% human-written result.
But more than occasionally, some tools can give me an AI-generated result or partial score, even when I know my writing is 100% mine.
On the other side of the coin, when I check a sample text that I generate from ChatGPT or Gemini, some tools can give a high human score.
That’s why you can’t trust the job to one tool.
Even Grammarly, which is an expensive premium writing tool, can get the result wrong.
I haven’t included it in my list of tools below because it is not free. But as I have a subscription, I use its AI detector occasionally.
For most writers, and in most cases, free tools are your best option.
Your choice of free AI-detector tools
If you do a search online, you can find plenty of these tools.
Some are better than others, and they vary considerably in how many words or characters you can check. That’s why it’s a good idea to bookmark a few to use when you need them.
I chose ten detection tools to check for this article, and used two 500-word texts.
I wrote one text about parallelism, and the other, I used ChatGPT to output a text on the same topic.
So, how do these tools perform?
I’ll give you the results for each text, but will only include images for a couple of them to save making this article a marathon.
1. Copyleaks
I use the Copyleaks AI-Detector & Content Checker quite often, because it is usually quite reliable.
Here are the results of my two sample texts. The first is the text I wrote, which scores 0% AI.
Now for the AI-generated version, scoring 100% AI.
It’s the result I expected, and it’s a good example of why I use this tool regularly.
However, from experience, it can produce false positive results.
2. Dupli Checker
The Dupli Checker AI-Content Detector is another one I use regularly.
Results of my two texts:
My text: Human content score 100%
AI Text: AI-written content 0%
As you can see, this was a big miss by this tool. It judged that the obviously AI-generated text was 100% human-written.
It’s a pity, because this tool can work better. But in this instance, it’s a good example of why you can’t rely on one tool.
3. SurferSEO
Here are the results for the SurferSEO AI-detector.
My text: 93% AI and 7% human.
AI text: 4% AI and 96% human.
Well, that was an almost 100% failure to detect the texts correctly. It’s so bad, that I ran the tests twice to be sure.
4. Writer
Let’s see how the Writer AI detector performs.
My text: 91% human.
AI text: 88% human.
Again, a false positive for my sample AI text.
5. Originality
Now, on to the Originality.ai checker.
My text: 97% human.
AI text: 100% AI text.
You can see that this tool gave an accurate result, so it’s probably worth using.
6. Scribbr
Next on my list is the free AI Detector from Scribbr.
My text: 0% AI text.
AI text: 81% AI text.
A reasonably accurate result from this tool.
7. QuillBot
You probably know QuillBot as a grammar tool. But it also has an AI detector tool.
Here are the results.
My text: 0% AI text.
AI text: 81% AI text.
The same result as Scribbr, which makes me think that it’s the same tool.
8. Phrasly
The AI detection tool by Phrasly is a new one for me. Let’s see how it goes.
My text: 42% AI text.
AI text: 60% AI text.
Not a great result with this tool. I would have it low on my list of apps to use.
As an aside, after testing this app, I was plagued by ads for this tool on almost every site I visited, including CNN.
That’s why I haven’t included a link to this tool. But if you want to try it, you can search online.
9. JustDone
The AI Detector by JustDone is another new app for me. So, how does it perform?
My text: 84% AI text.
AI text: 75% AI text.
Another poor result, so I wouldn’t suggest relying on this tool.
10. NoteGPT
My last stop is the Free AI Detector by NoteGTP.
My text: 42% AI text.
AI text: 64% AI text.
Not very good result, but better than some other tools.
One last check
For comparison, I ran my test through Grammarly’s AI detection tool.
My text: 0% AI text patterns.
AI text: 33% of your text has patterns that resemble AI text.
Not a bad result, but I would have thought the AI score would be higher.
If you don’t have a Grammarly premium account, the results don’t seem to be worth the expense if you are determined to find a reliable checker.
Summary
As you can see, the results from my tests vary considerably for these tools.
While some are somewhat accurate, others are way off the mark, and some are a waste of time.
That’s why you can’t rely on any one tool to give you accurate results for checking human or AI-generated writing.
An extra factor is that the results can be different from one text or check to another.
I didn’t include this in my results, but when I tested four different AI texts, most tools varied from 0 to 100% depending on which text I checked.
That’s why these tools are only useful as an indication, and why it’s always best to check with a few.
If you are a writer, it’s not a bad idea to do a check. It can highlight one or two sentences that may seem a bit robotic, so you can improve or rewrite them.
But don’t worry if your writing gets a poor AI score on any of the tools, because they are not at all 100% reliable or accurate.
One last consideration is that AI writing is improving every day, so it may become increasingly difficult soon to rely on any tools to conduct a check.
Related Reading: Why Using AI To Write For You Is A Terrible Idea
