Isgen AI Detector Review: 3 Tests That Show Its Accuracy

Isgen AI detector is designed to spot whether text is written by humans or generated by AI. But how accurate is it really? 

In this review, we put Isgen through three tests—pure AI writing, mixed human + AI text, and humanized AI content—to see how well it performs. 

Along the way, we’ll cover its strengths, weaknesses, pricing, and whether it’s worth using for students, teachers, and writers. Let’s dive into the results and see if Isgen lives up to the hype.

What is Isgen? 

Isgen is an AI-powered tool designed to help students and content creators. It aims to make writing more transparent and trustworthy, especially in academic and professional settings.

What is Isgen AI Detector?

The Isgen AI detector is trained to recognize writing patterns from major AI models like ChatGPT, GPT-4, Claude, DeepSeek, and Gemini. It provides detailed phrase and sentence-level feedback. Users can either paste text directly into the platform or upload full documents, and the tool supports content written in more than 80 languages.

Beyond detection, Isgen includes a set of extra tools, such as plagiarism detection, a grammar checker, a citation generator, and even batch checking for larger projects.

How Accurate is Isgen AI Detector?

Isgen claims to deliver high accuracy in detecting AI-generated writing. To test this, we ran several experiments using different types of text. The aim was to see if its results align with the actual source of the content.

Test 1: Pure AI Text

Setup: We used a passage written entirely by ChatGPT-5, with no human edits.
Results: Isgen flagged the text as 100% AI-generated.

Observations:

The tool correctly identified the text, matching the reality of its origin. This shows that Isgen is reliable when handling content that is fully produced by AI without human involvement.

Test 2: Mixed AI + Human Writing 

Setup: We used a paper originally written by humans before ChatGPT was released, then continued the text with ChatGPT-5. The final sample had 454 words in total, with 187 words (41%) written by humans.

Results: Isgen identified the text as a mix of human and AI, reporting 59% AI content.

Observations:

The result aligns with the actual composition of the text, showing that Isgen can effectively detect blended writing and give a balanced percentage breakdown.

Test 3: Humanized AI Text by QuillBot

Setup: For the final test, we used QuillBot’s AI Humanizer (Basic Mode) to rewrite the text that was fully generated by ChatGPT-5 in Test 1. The goal was to see if Isgen could still detect AI after the text was rephrased to look more natural.

In this setup, the Humanizer only applied light paraphrasing and word substitutions without making deeper structural or stylistic changes.

Results: Isgen flagged the passage as 100% AI-generated.

Observations:

This result suggests that Isgen can still recognize text that has been only slightly humanized.

QuillBot’s basic rewriting did not significantly alter the underlying language patterns—such as sentence predictability and burstiness—which continued to reflect machine-like consistency.

As a result, Isgen was able to detect the AI origin despite the surface-level paraphrasing.

Pros and Cons of Isgen AI Detector

Like most AI detectors, Isgen comes with both strengths and weaknesses. Below, we summarize its key advantages, drawbacks, and what users should know.

Pros:

• Accurate results, fast turnaround: The platform processes text fast, which is helpful if you’re on a deadline and need immediate feedback.

• Detects AI at both the phrase and sentence level: Instead of only giving a single percentage score, Isgen highlights specific phrases and sentences, making it easier to see exactly where AI content may appear.

• Multilingual support: This makes it a strong choice for international students and multilingual writers who need detection beyond English.

Cons:

• Occasional false positives: Some users have reported that entirely human-written text can occasionally be flagged as AI-generated, which may cause frustration.

• No online editing support: While it highlights issues, users can’t directly edit text inside the platform and must revise elsewhere.

• Limited free plan: The free version only allows AI detection. To use plagiarism checks or other features, users need a paid subscription, which limits convenience.

Isgen AI Detector Pricing

Free Plan

• Allows up to 6,000 words per check.

• Limited trial access with only the basic detection mode enabled.

Paid Plans

Isgen integrates its AI detector into tiered paid plans, starting at $9 per month. Higher plans expand functionality with more advanced features:

• Increased word limits per check.

• Advanced AI detection system, including phrase-level analysis for pinpointing AI-generated content more precisely.

• Advanced plagiarism checker for originality verification.

• Batch file upload support for processing multiple documents at once.

• Additional tools such as grammar checking and priority access.

Can You Bypass the Isgen AI Detector?

So, can Isgen be bypassed? The answer is yes—but not with quick fixes. Isgen is designed to catch surface-level tricks like word swaps, minor edits, or simple paraphrasing. In our Test 3 with QuillBot’s basic mode, the lightly rephrased passage was still flagged as 100% AI-generated, proving that easy methods don’t work.

To get past Isgen, the rewriting must go deeper—changing not just words, but the sentence structure, phrasing, and overall rhythm of the text. That’s where specialized AI “humanizers” come in. EssayDone Humanizer, for example, goes beyond synonyms and actually reshapes the language flow to resemble authentic human writing.

We tested this directly: when the fully AI-generated text from Test 1 was processed through EssayDone Humanizer and rechecked with Isgen, the detection score dropped dramatically—from 100% AI down to just 11% AI-detected. This shows that only structural-level rewriting, not superficial edits, can reliably bypass Isgen.

Alternatives to Isgen AI Detector

FAQ

1. Is Isgen 100% accurate?

No AI detector is perfect. Isgen is highly accurate, especially with fully AI-generated text, but results may vary for mixed or heavily humanized content.

2. How to bypass Isgen AI detector?

Simple rewriting or synonym swapping won’t work reliably. Tools like EssayDone Humanizer that restructure sentences and adjust style can reduce detectable AI markers.

3. Will my professor use an AI detector?

Many educators are adopting AI detection tools, but usage varies by school and instructor. It’s always best to check your institution’s policy.

4. Can I use AI detectors on my own work before submission?

Yes. Checking your text before submitting can help you identify and revise sections that may be flagged as AI-generated.

5. Are AI detectors legal?

Yes. Using AI detectors for academic integrity or personal checks is legal, as they do not violate copyright or privacy laws when used properly.

6. Is Isgen AI Detector free?

Yes, Isgen offers a free plan with a 6,000-character limit per scan, but advanced features require a paid subscription.

Conclusion

In this review, you’ve seen what Isgen is, how its AI detector works, and how accurate it can be when tested with pure AI, mixed AI-human and humanized text. 

We also covered its main features, pricing, and common questions that users often have.  Hopefully, this article gives you clarity and helps you better understand AI detection tools.