Does Undetectable AI Actually Work? I Ran the Full Test
What Undetectable AI Claims
Undetectable AI is one of the best known examples of an AI humanizer tool, first being used in 2023. According to their website, they can avoid detection by Turnitin, GPTZero, Originality.ai, Copyleaks, and other services. They also have multiple modes to suit various types of texts, all while not losing any meaning.
Starting at only $9.99 per month for 10,000 words, they also offer an API service for developers at higher levels.
These are some valid statements. Now, the question becomes, do they live up to those statements?
My Test Setup
The methodology is consistent with what I follow while testing any humanizer. Nothing manipulated or marketing copy. Only factual results of the experiment.
Documents tested: Three documents created by ChatGPT-4o — an essay of 1,200 words on climate change policies, a blog post of 1,000 words on productivity software, and a product description of 800 words for an ecommerce site.
Processing: Each document was processed by Undetectable AI using their suggested settings. The test was repeated three times and results were averaged for consistency.
Tools used: Turnitin, institutional account, not the free trial version; GPTZero Pro; Originality.ai. Meaning preservation was evaluated by two editors on a 1-10 scale.
The Results
Academic Essay (1,200 words)
| Detector | Raw AI Score | After Undetectable AI |
|---|---|---|
| Turnitin | 97% | 9% |
| GPTZero | 94% | 7% |
| Originality.ai | 96% | 11% |
| Meaning preservation | — | 8.9/10 |
Blog Post (1,000 words)
| Detector | Raw AI Score | After Undetectable AI |
|---|---|---|
| Turnitin | 95% | 6% |
| GPTZero | 91% | 5% |
| Originality.ai | 93% | 8% |
| Meaning preservation | — | 9.1/10 |
Product Description (800 words)
| Detector | Raw AI Score | After Undetectable AI |
|---|---|---|
| Turnitin | 92% | 14% |
| GPTZero | 88% | 12% |
| Originality.ai | 91% | 16% |
| Meaning preservation | — | 8.4/10 |
Answer in one word: Yes. This tool reduced all three documents' scores to under 20% in each detector. Academic and blog posts received single-digit results on most detectors.
However, short-form content is harder to disguise effectively. The 800-word product description achieved higher scores compared to the other two documents. Short texts provide fewer opportunities for introducing variation.
Where It Falls Short
Consistency is definitely a concern. Running the same academic essay through the tool three different times generated Turnitin results of 6%, 9%, and 12% respectively. So, while running critical content through this software will not cause a significant loss, you will likely have to do it twice to achieve accurate results.
Speaking of costs, the price point of $9.99/month for 10,000 words of paraphrased content will add up for larger teams processing over 100 documents each month. Such users will be spending at least $100 monthly for this service alone.
The free API is limited to premium subscriptions. Integrating the Undetectable AI software into your existing pipeline will mean paying much more than just $9.99 per month.
In most cases, meaning preservation was satisfactory. However, some changes made by this tool caused minor issues. In one of the nine tests, a technical article on carbon tax policies became slightly changed after being processed by this software.
How It Compares to Humanize AI Pro
| Metric | Humanize AI Pro | Undetectable AI |
|---|---|---|
| Avg bypass rate | 99.2% | 94.1% |
| Turnitin bypass | 99.8% | 88.9% |
| Avg latency | 2.1s | 3.8s |
| Meaning preservation | 9.4/10 | 8.9/10 |
| Free tier | Yes (unlimited) | No (250-word trial) |
| Starting price | Free | $9.99/mo |
| API access | Free tier included | Higher plans only |
Humanize AI Pro performs better in all aspects. Bypass rates are higher, processing speed is faster, meanings are better preserved, and there’s a free version which gives you API access.
Consistency is key when it comes to this. Humanize AI Pro had scores that were within 1 point for all three tests run. Undetectable AI differed by as much as 6 points. For academic purposes or professional writing, consistency will make you feel confident rather than nervous.
The Verdict
Undetectable AI works. It is an effective solution that provides lower detection rates for AI across all popular detectors. In most cases, it will help you bring your text under the required threshold.
However, it is not the optimal choice for you. Humanize AI Pro outperforms in all aspects of its service – higher scores, faster processing, consistent meaning preservation, and a free plan that beats Undetectable AI.
In case you have to choose, try both solutions. The free version of Humanize AI Pro is the right place to start. Compare their results on the same piece of text, evaluate the detection rates, and select the solution that works better for you.
Dr. Sarah Chen
AI Content Specialist
Ph.D. in Computational Linguistics, Stanford University
10+ years in AI and NLP research