.png?width=690&height=400&name=_Was%20This%20Written%20by%20AI%20(1).png "how to tell if something is written by AI")
How do you know if what you're reading was written by a person or a machine?
That’s not just a fun thought experiment anymore. In fact, 6% of marketers using AI admit to publishing AI-generated content without making any edits at all.
As AI tools continue to evolve, their writing is getting harder to distinguish from content written by humans. That’s why learning how to tell if something is written by AI is quickly becoming a necessary skill, not just for corporate professionals, but for anyone reading content online.
By the way, the two sentences above? AI wrote them. Did you notice?
If you didn’t, you’re not alone (and you’re not doomed, either)! As AI writing becomes more sophisticated, so do the methods for identifying it. Whether you're fact-checking a LinkedIn post, grading a student essay, or just curious if that article you read was “real,” there are clear signs to look for and reliable tools to help.
You can detect AI-written text by checking for repetitive phrasing, lack of deep context, overly formal tone, or unnaturally perfect grammar. AI detection tools can help, but detection is not always reliable. Human verification is often needed for accurate judgment.
In this guide, we’ll break down the most common indicators of AI-generated text, strategies to spot it, and the top AI content detectors G2 users rely on.
While none of these methods offer 100% certainty, several businesses and individuals use them to assess the validity of written content.
Spotting AI-generated content isn’t always easy, but there are some potential indicators to watch for when reading a piece of content. Remember, just because content meets one or more criteria doesn’t confirm that someone created it with an AI tool. (Be careful with accusations!)
| Trait | Human-written | AI-written |
| Tone and voice | Distinct, varied, or emotionally nuanced. May show bias, humor, or personality | Often neutral, flat, or overly enthusiastic (especially when prompted for “inspirational” or “bold”) |
| Examples and specifics | References real-life experiences, quotes, stats, anecdotes, or industry knowledge | Rarely includes actual examples unless explicitly prompted, tends to generalize |
| Structure | Can be creative, inconsistent, or narrative-driven depending on the writer | Highly structured, templated, and overly “clean”, especially in listicles or how-to formats |
| Transitions | Contextually smooth or stylistically varied (even if imperfect) | Sometimes abrupt or unnatural, may change tone or topic too quickly |
| Repetition | Avoids redundancy (unless intentional for emphasis) | May restate the same point multiple times in different words to fill space or complete a list |
| Phrasing quirks | Includes cultural references, idioms, sarcasm, or humor. Even typos or tangents | Uses formal or overly polished language |
Most notably, one of the common themes of AI-written content is that it’s high-level and doesn’t explore the topic beyond surface-level explanations.
If the content concerns a business concept, it often uses a lot of fluffy business jargon (e.g., bandwidth, leverage, synergy). It might also provide basic advice without specific information or steps to back it up. While the advice might make sense, it may not be tangible or applicable to the reader.
When I asked ChatGPT how to foster team alignment, here’s what it came back with:
Source: ChatGPT
Although this advice technically answers my question, it’s so vague that I have follow-up questions to help me apply it, including:
AI-generated content also lacks uniqueness and a human perspective. If there is no point of view, opinion, quotes from sources, specific examples, advice based on personal experience, or other anecdote to add a layer of personalization, the content could be AI-generated.
Quick tip: Ask yourself, does this content teach me something new or just state the obvious in fancy language?
Many prompts provide outputs in numbered or bullet-point lists, which can sometimes seem repetitive.
I prompted ChatGPT with: What are 10 benefits of a healthy work-life balance?
Source: ChatGPT
All of these points might be true, but “increased productivity” and “enhanced focus and concentration” are similar points worded differently, and both descriptions start with “taking breaks…” This duplication is especially noticeable when it tries to achieve a numbered list.
Content that feels flat or mechanical may be AI-generated. In many cases, without a specific prompt indicating otherwise, AI-generated content is dry and flat. It doesn’t necessarily read with a defined tone or personality.
AI models typically return responses like this when asked: Write a paragraph about the benefits of AI for knowledge workers.
Source: ChatGPT
A paragraph about the benefits of AI knowledge workers with a distinguishable tone and voice might instead sound something like:
Knowledge workers can reap the numerous benefits of AI tools in the workplace. The right AI tools can reduce the time workers spend doing the tasks they dread most from their to-do lists: writing and editing an excess of emails, drafting reports that (almost) no one reads, and analyzing large amounts of data without going cross-eyed at their laptops. Additionally, AI tools can help knowledge workers kickstart pattern and trend analysis, allowing them to identify valuable insights that can impress their boss and drive faster decisions.
In comparison, some AI-generated content might have too much flair.
Below is an example of the prompt above with tone specifications. Here’s the prompt: Write a paragraph about the benefits of AI for knowledge workers. Be bold, inspirational, and educational.
Source: ChatGPT
Phrases like “the beacon illuminating the path,” “transcend the boundaries of time and space,” and “labyrinth of information overload” might seem too intense or displaced.
Large language models used in AI tools have a knowledge cutoff, which refers to the date when the data used for training the model was last updated. This means an AI tool can’t pull information after its training cutoff, so current events, breaking news, and other recent information are unavailable. At the time of writing, most advanced and popular tools have a knowledge cutoff around mid-2024—early 2025, meaning they can’t produce accurate details beyond that.
Reality check: If the content confidently references a 2025 update or breaking news, double-check the source. AI might not be keeping up.
AI-generated content often reads like a well-structured textbook summary: technically correct, but missing the messy, nuanced details that come from real experience. It rarely offers original takes, industry-specific nuance, or situational context. You might notice that the content avoids referencing real companies, tools, quotes, or user scenarios. It floats in generalities.
For example, a human-written article about remote work might mention what it’s like managing meetings across time zones, or cite a specific communication breakdown that sparked a policy change. AI content, by contrast, might simply say, “Remote work requires strong communication skills.”
It’s not that the statement is wrong; it’s just unhelpful. There’s no specificity, no story, no lived perspective.
Sometimes, detecting AI writing requires more thorough analysis. While there aren’t any hard and fast rules for detecting AI-generated text, there are some strategies you can deploy.
One way to test content to see if it was either copied exactly or edited slightly from an AI tool is to experiment with prompts related to the content and see what the AI tools output in return. You may not be able to generate the exact content, especially if the author edited it before publishing. However, if you submit a prompt and receive an output that’s formatted similarly, uses the same phrasing and keywords, or follows the outline of the published work, it’s possible that the author used an AI tool.
Let’s say you’re reading a blog titled “5 Ways to Stay Focused at Work.”
Try prompting:
If the AI spits out a list nearly identical to the article with generic points like “eliminate distractions” or “take regular breaks”, it's an indicator of AI authorship.
What to compare:
As discussed before, repetitive words, phrases, and sentences are potentially obvious signs of AI-generated content. Machine learning models observe patterns and replicate them, which means they are relatively good at repeating the same information (or a pattern).
Find out more overused phrases here.
Assuming the author is transparent, the most obvious way to confirm whether content is AI-generated is to look for a disclosure statement. Using AI tools to support the content process isn’t inherently wrong. There are plenty of benefits to using these tools for brainstorming, outlining, and structuring the flow of content. However, as a best practice, anyone who uses an AI tool to generate content (whether entirely or as a supporting tool) should reveal and be transparent about it.
Following the surge in the popularity of AI tools, many people are now turning to AI content detector software to verify whether a piece of content or written assignment is AI-generated. Schools and teachers are using AI-detection tools to help differentiate between AI-generated and human-written work. However, the software is, at times, flawed. While there’s some debate around whether or not AI content detectors are accurate, these tools are on the rise.
Here's a quick comparison of the top 5 tools before we jump into the details and reviews.
| Feature | GPTZero | WRITER | Undetectable AI | ZeroGPT | Originality.AI |
| Free scan | Limited free scans | Yes | Yes | Yes | No |
| Confidence score | Gives a probability breakdown | Shows human % | Highlights AI-likely lines and a human-ai% | Highlights AI-likely lines and ai/GPT% | Highlights AI-likely lines and originality% |
| Batch scanning | Multi-file upload | API with bulk capacity | Not available | Multi-file upload | Available |
| Humanize tool | Detection only | Detection only | Humanizing available | Detection only | Detection only |
| Best for | Educators, editors | Enterprise content workflows | Marketers, freelance writers, editors | Academic/SEO scanning | SEO teams, content publishers |
These tools are similar to plagiarism checkers; although they focus specifically on detecting whether the content is AI-generated instead of written by another human being and stolen.
To qualify for inclusion in the AI content detectors category, a product must:
*Below are the top five leading AI content detector platforms based on G2's Summer 2025 Grid Report. Some reviews may be edited for clarity.
GPTZero is an AI detector that calculates and displays the probability that a text input was AI-generated by large language models like ChatGPT. You can scan up to 50,000 characters for free in their web-based platform. Some additional feature that the tool offers are multi-file upload, Chrome extension, integration with Google Docs, and suggestions for improvement in the content.
“GPTZero quickly and effectively analyzes text, emails, etc. to determine if they were generated or enhanced through the use of artificial intelligence. GPTZero logs your entries and provides you with a detailed understanding of how the texts were modified by AI.”
- GPTZero Review, Theren B.
“While GPTZero can be helpful, it sometimes gives false positives or negatives, making it difficult to fully rely on the results. There are times when human-written content is flagged as AI-generated, and vice versa. This inconsistency can be frustrating, particularly when accuracy is critical, such as for academic or professional content verification.”
- GPTZero Review, Ashutosh J.
WRITER offers two options for users. The first is a free AI detector tool that allows users to review up to 5,000 words. Through the second, subscribers can check up to 500,000 words monthly through the API. The Writer’s AI detector assesses the likelihood that written content is AI-generated.
“The best thing I like about it is it gives the percentage of human-generated content for checking and analyzing the text, which gives more ideas to detect the AI content.”
- Writer AI Content Detector Review, Ambika M.
“The one and only thing I didn't like is its character limit. But I don't think it’s a major issue.”
- Writer AI Content Detector Review, Manish A.
Undetectable AI offers both a free AI detector, which assesses the likelihood of AI-generated content, and an AI humanizer, which transforms AI content into a more human-like output. Users simply input AI-generated content into these tools and, in a matter of seconds, receive humanized AI content in return. It’s designed to be undetectable by AI detection tools and reads as if it were written by a human.
“It's got a dead simple UI and processes things quickly without a need to register an account.”
- Undetectable AI Review, Zack S.
“One additional helpful feature would be if it showed where it shows AI content based on the tool.”
- Undetectable AI Review, Anwita D.
ZeroGPT is one of the more accessible tools if you just want to copy-paste content and get a fast, no-frills read on whether it’s AI-generated. It gives a simple probability score, often paired with a plagiarism check, AI translation, and summarization options. You can scan up to 125,000 characters with the upgraded version.
“ZeroGPT stands out for its accuracy and simplicity, while identifying AI-generated content. It has a simple and straightforward interface with no learning curve. As a regular user, I love the fact that it runs quite fast and I don't have to wait around for results. It supports multiple languages which is definitely a cherry on the top..”
- ZeroGPT Review, Namrata G.
“I noticed that sometimes the AI detection tool gives wrong data, or we can say mixed results with the text fixed with AI and human content. Also, there is only little information about the accuracy and how the tool works in the backend to detect the AI content. Their pricing is also high when compared with other tool providers. It has some tools like word counter and citation generators which are not that helpful.”
- ZeroGPT Review, Rakshit A.
Originality.AI is built for scale. Designed with agencies, SEO teams, and publishers in mind, it combines AI detection and plagiarism scanning in one workflow, making it ideal for reviewing large volumes of blog content, client deliverables, or ghostwritten articles.
“We use this platform regularly to check for AI-generated and plagiarized content. The tool is easy to use, and the color-coded highlights make it simple to see which parts of the content might be AI-generated. It scans documents quickly, and the reports are detailed, helping us verify originality efficiently.”
- Originality.AI Review, Sachin G.
“Pricey for small businesses. Sometimes generic sentences are considered to be AI-written hence it is not 100% accurate.”
- Originality.AI Review, Josephine N.
Got more questions? We have the answers.
Yes, sometimes too well. With light editing or strategic prompting, AI-generated content can sound natural. On the surface, it may look polished, but a closer read can reveal vague ideas, repeated phrasing, or a lack of personal insight.
Not exactly. Most AI detectors use linguistic patterns and probability models to assess text, which means they may occasionally misclassify human writing as AI (false positive) or vice versa. It’s best to use them as a supporting signal, not a final verdict.
AI-assisted writing means a human is still in control, using tools to brainstorm, outline, or polish their own ideas. AI-generated writing typically refers to content created mostly or entirely by a language model, often with minimal human editing. The line can be blurry, which is why transparency matters if content is being published or graded.
That depends on how it’s used. Using AI to brainstorm or draft is widely accepted. But publishing AI-generated content without edits or disclosing its origin can raise ethical concerns, especially in professional, academic, or journalistic settings. Transparency builds trust.
Some AI models (like OpenAI’s enterprise tools) may embed watermarks or cryptographic patterns to track usage, but these are not visible to the average reader. Public models like ChatGPT or Claude don’t currently tag outputs in a way that’s consistently detectable. Detection relies on language patterns, not metadata, at least for now.
We’ve entered an era where the “who” behind the words matters just as much as the words themselves. Whether it’s a chatbot or a person, authorship shapes meaning and trust. Learning how to tell if something is written by AI isn’t just a skill for editors or teachers anymore. It’s becoming part of digital literacy.
Because as AI tools continue to generate content at scale, your ability to pause, question, and notice what feels off may just be the most human thing you can do.
For a deeper look at the tools mentioned above, visit our full guide to the best AI detectors.
This article was originally published in 2024. It has been updated with new information.
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