Is That Text AI or Not: What Does AI Score Mean?

AI detection scores: what are they, and what do they mean?

In this guide, we’ll take a look at one aspect of how AI detectors work: the AI score and what an AI score means. 

In brief, an AI detection score (also known as an AI score) is the score that an AI checker provides after scanning text. It indicates whether the text was Likely AI, human-written, or Mixed writing.

Keep in mind that the method for presenting (and determining) AI detection scores can vary by brand and AI detector, or type of AI detection software.

Here, we’ll focus on the industry-leading Originality.ai AI Checker and what the Originality.ai AI detector score means.

What is an AI Score? The Quick Answer

At Originality.ai, AI scores show the percentage of your text that is Likely AI, Likely Original, or Mixed writing, so that you can see how much of your writing involves AI.

5 Key Insights About AI Scores

1. Originality.ai 5.0 and 5.0 Max show the percentage of AI involvement in content and whether it’s Likely AI, Original, or Mixed writing.
2. Sentence-level highlighting clearly shows what’s Likely AI.
3. Originality.ai 5.0 and 5.0 Max are highly accurate.
   
   • Read more: Accuracy Study + Third-Party Studies + Introducing Originality.ai 5.0
4. False positives do occur in AI detection:
   
   • Use our Browser extension to watch the entire writing process.
   • Learn about our False positive bounty program.
5. Plagiarism and AI scores are different:
   
   • Plagiarism detection identifies instances of plagiarism (such as matching text from other sources).
   • AI detection determines whether or not a text was likely human-written or AI-generated.

What Is an AI Detection Score?

Our AI detector provides an AI Score that shows the percentage of AI involvement in a piece of content, and then classifies it as Likely AI, Original, or Mixed writing. 

How to See What Parts of a Text are Most Likely AI

Once the Originality scan is complete, you can dig deeper beyond the AI score.

We provide sentence-level highlighting showing what parts the Originality AI Detector found were the most likely to be AI-generated. 

• If your text is human-written, it will have Dark Green highlights that indicate the sections which are likely original.
• If your text is AI-generated, it will have Dark Red highlights that indicate the sections which are Likely AI.

To demonstrate the in-text highlighting, we prompted ChatGPT to generate 15'0 words on digital marketing:

Then, when we ran that through the Originality.ai AI Detector, you can clearly see the ChatGPT-generated text highlighted in dark red to indicate that it is Likely AI.

Now, let’s compare that with some original content, written by a human from the beginning of this article.

Note: The patterns that our AI picks up on cannot be translated into a simple list of ‘here are x reasons why your content is identified as AI-generated’.

How Does Our AI Detector Work?

Wondering how AI detection works? Our AI detector takes a holistic and intensive approach to analyze an article to determine if it was AI-generated. Read our in-depth article: How Does AI Content Detection Work? for more insights.

Is the Originality.ai AI Score Accurate?

Yes, our AI detector has demonstrated exceptional accuracy in both internal tests and multiple 3rd-party studies:

• Our Internal Accuracy Study
• Meta-Analysis of 3rd-Party Studies (identifying Originality.ai as the most accurate)

Is the score perfect? 

At Originality.ai, our machine learning engineers are always running tests on the latest AI models (such as GPT-6 Astra).

However, no AI detection tool is perfect. The tool can produce incorrect predictions and predict that content that was human-written is AI-generated (also known as a false positive - more on that later in this guide).

Which AI Detection Model Should I Use? 

Originality.ai provides distinct models that are tuned to meet the needs of specific use cases. 

The AI detection models that are currently available include: 

Originality.ai 5.0

• 99%+ Accuracy

Originality.ai 5.0 Max

• 99%+ Accuracy

What if an AI Detector Thinks Something I Wrote was AI-Generated? This is Called a False Positive.

False positives are painful when they occur, and we are working hard to continually drive down false positive rates. 

A false positive occurs when an AI detector thinks something was AI-generated when, in fact, it was written by a human. 

How Can I Reduce the Risk of False Positives?

We offer Browser extensions to assist in transparently showing you the writing process that truly created it (whether human-written or AI-generated).

We appreciate the valid question, “Why was my article identified as AI?” Below are resources on how to prevent and reduce the risk of false positives.

• How to Prevent False Positives
• How to Deal with Accusations of Using AI
• Does Using Grammarly Make My Content Get Detected as AI-Generated?

Plagiarism Scores vs. AI Scores: Are They The Same?

The answer is no. 

A Plagiarism Checker provides hard proof that plagiarism occurred, while an AI Detector provides a score on whether text is Likely AI, (Original) human-generated, or Mixed writing.

Here’s a quick look at some of the differences between plagiarism checking and AI detection:

The same approach should not be taken with Plagiarism and AI detection. For instance, a text might be AI-generated but not include plagiarism. Alternatively, a plagiarized article might be human-written.

Is using AI plagiarism? 

This is a complex question. AI detection and plagiarism checking are different, just as we outlined in the chart above.

The concern around AI plagiarism typically surfaces around training data issues. While AI typically generates content that is new, OpenAI is facing 50+ lawsuits, including cases involving copyright or training data. 

So, it’s important to review AI-generated content carefully to make sure the copy doesn’t closely replicate existing material as a result of training data concerns.

Further Reading

Learn about AI Detection and AI Detection Accuracy:

• AI Content Detector Accuracy Review
• AI Detection Accuracy Studies — Meta-Analysis
• AI Content Detector False Positives
• How Does AI Content Detection Work?
• Can Google Detect and Does it Penalize AI Content
• Plagiarism Accuracy Study

Learn about the impact of AI across industries:

• How Originality.ai Could Have Prevented the AI-Generated Book List Scandal
• Politician Reading AI Residue Reveals a Larger AI Pattern
• 37% of Canadian Real Estate Listings are Likely AI

AI Studies on Recent LLMs

• Gemini 4 Argon
• GPT-6 Astra
• GPT-5.6 (Sol, Luna, Terra)
• Grok 4.6
• Gemini 3.7 Flash
• DeepSeek V4 Pro
• Kimi K3