Best AI Detectors in 2026: 11 Tools Tested on AI, Human, and Mixed Writing

Lisa Braswick

AI Content Specialist

Published: 20 December 2024 Updated: 26 October 2026

30 min read

Last updated: October 2026. Tested on ChatGPT (free version) output, human-written samples, and AI text paraphrased by a real person.

Every AI detector claims to be the most accurate AI detector on the market. Almost all these statements are based upon raw data or completely unedited AI output, both of which are the easiest type of text to identify as AI-generated.

We were interested in finding out if the best AI detectors would perform similarly well when subjected to the same writing submitted by actual humans. So we took 7 writing samples, which included pure AI, pure human, and an AI article that a person rewrote by hand, and ran them through 11 AI detection tools. All of the results shown in this guide were generated during that test, including each tool’s score and threshold limit. Screenshots of every result are included in each tool’s entry below.

Quick Verdict: The Best AI Detectors in 2026

Quick verdict: Walter Writes, Proofademic and Originality.ai are the best AI detectors in 2026

Most of the other detectors performed with high accuracy on the clear-cut examples. The real difference was shown when they were tested using a mixed sample, and only three of them made it through every test.

Top picks:

Walter Writes (best AI detector overall): Passed all seven tests, flagged every AI sample at 99%, kept every human sample at 1% or lower, and caught the hand-paraphrased sample at 90%. It costs $8 per month if you pay annually.
Proofademic (best AI detector for teachers): Got the highest mixed score out of all of our ranked tools, 93%, and had no human samples above 1%. Starts at $8 per month if billed annually.
Originality.ai (best for bulk scanning): The only other tool to pass all seven tests, with 90% on the mixed sample and strong bulk scanning. Its mixed-sample pass came after a mid-test update to the tool. Starts at $12.95/month, billed annually.

Quick Decision: Which AI Detector Should You Use?

You’re a student checking an essay before submission: Walter Writes, the AI detector for essays that kept all human writing at 1% or lower.
You’re an SEO writer checking ChatGPT drafts: Walter Writes was able to detect both raw and rewritten AI.
You’re a teacher reviewing student work: Proofademic is designed specifically for academic work, and it has the highest detection rate against paraphrased AI.
You run an agency that scans content in bulk: Originality.ai.
You work with scanned or printed documents: Pangram.
You check text in languages other than English: Copyleaks.

Refine your draft

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Full Comparison Table of 11 AI Detectors

Accuracy shows how many of the seven tests each tool passed under the thresholds explained in our method. A “moderate” result is neither a pass nor a fail.

Rank	Name	Accuracy	Free Available	Pricing Starts From (Annually)	Best For
1	Walter Writes	7/7 passed	✅ Yes	$8/month	Students, ChatGPT and SEO content
2	Proofademic	7/7 passed	✅ Free trial	$8/month	Teachers and academic work
3	Originality.ai	7/7 passed	✅ Yes	$12.95/month	Bulk scanning
4	Pangram	6/7 passed, 1 moderate	✅ Yes	$15/month	Scanned documents (OCR)
5	GPTZero	6/7 passed	✅ Yes	$12.99/month	Quick one-off checks
6	QuillBot	6/7 passed	✅ Yes	$8.33/month	Paraphrase-and-check workflows
7	Copyleaks	6/7 passed	✅ Yes	$13.99/month	Multilingual text
8	Undetectable.ai	5/7 passed, 1 moderate	✅ Yes	$5/month	Pre-rewrite scans
9	Grammarly	5/7 passed, 1 moderate	✅ Yes	$12/month	In-editor checks
10	ZeroGPT	5/7 passed	✅ Yes	$8.99/month	Large document uploads
Unranked	Sapling*	Not comparable	✅ Yes	$12/month	Enterprise API integration

*Sapling’s free plan scans only the first 2,000 characters of each sample, so its results can’t be compared directly with the other tools. See its entry for details.

How We Tested

In order to make the test data comparable among all detectors, we ran all tests under the same conditions.

Testing Methodology

Three content types: Academic essays, creative writing, and social media (LinkedIn) posts
Two baseline samples per type: The first was created using a free version of ChatGPT in October 2026. None of these samples were edited or altered by humans. The second baseline sample was an example of the same type of content that is written by a real person.
One mixed sample: We also used a mixed sample, which was a blog generated by ChatGPT that our team member paraphrased manually by rewriting each line.
Same text for every tool: Each detector scanned the exact same samples and there were no edits made between the different tools.
Screenshots of every result: We took screenshots of each detector’s results so you can see the numbers behind the tables.

Why the Mixed Sample Matters

The mixed sample was an article created using ChatGPT. Our team member then reworded this article by hand, with each individual line rewritten by them without checking how it would score on any detector. This was to see how well a detector could find the AI usage underneath a humanized text.

This reflects how AI is historically employed for real-world purposes. In a 2026 study of 1163 master’s theses, most theses that Pangram flagged showed partial AI use rather than fully generated text. This is the test that separated the strongest tools from the rest.

Test Samples Used

AI Vs. Human Academic Essay:

AI Vs. Human Creative Writing:

AI Vs. Human Social Media Post:

Mixed Marketing Article:

Mixed test sample: AI-generated marketing article paraphrased by hand

Pass Thresholds

Any result is only considered a pass once the criteria listed below are met. A checkmark (✅) in each results table will indicate that the tool has completed this criterion.

Sample type	✅ Pass	⚠️ Moderate	❌ Fail
AI-generated	91 to 100% AI	50 to 90% AI	0 to 50% AI
Human-written	0 to 10% AI	11 to 50% AI	50 to 100% AI
Mixed	81 to 100% AI	60 to 80% AI	0 to 60% AI

Tools are ranked first by the number of tests they have completed, then by the fewest failures. Any remaining tied tests will be ranked based on which had the highest AI-generated average and then which had the higher mixed score. Each table provides all scores for each tool, allowing you to use your own threshold if you prefer.

Testing Limitations

Each content type used one AI and one human sample, and the mixed category used a single sample. Some free plans capped scan length, so we scanned as much as each allowed and noted it in the entry. Results reflect each tool’s version in October 2026. Pricing was checked on vendor sites on October 21 and 22, 2026.

1. Walter Writes: Best AI Detector for Students, ChatGPT and SEO Content

Walter Writes ranked as the best AI detector in this test, with the highest accuracy across all three content types. It flagged every AI sample at 99%, kept every human sample at 1% or lower, and caught the hand-paraphrased sample at 90%.

It is built for students checking essays before submission and SEO writers checking ChatGPT drafts before publishing. You get a percentage score with the AI-flagged sections, and an AI humanizer in the same workflow if a section needs rewriting.

Key Features

AI detection with a clear percentage score and flagged sections
Detection and humanizing in one interface
Support for 80+ languages
Free Chrome extension for checking text where you write
AI detector API and Claude MCP connector for platforms and workflows

Walter Stress Test Results:

Use Case	AI-Generated	Human written	Mixed Essay (AI Article →Human Paraphrased)
Academic Essay	99% AI ✅	1% AI ✅	90% AI ✅
Creative Writing	99% AI ✅	0% AI ✅
Social Media Post	99% AI ✅	1% AI ✅
Average	99% AI	0.6% AI	90% AI

Walter Results: AI Academic Essay

Walter Results: Human Academic Essay

Walter Results: AI Creative Writing

Walter Results: Human Creative Writing

Walter Results: AI Social Media Post

Walter Results: Human Social Media Post

Walter Results: Mixed Essay (AI Article → Human Paraphrased)

What These Results Mean

Accuracy on AI content: Walter Writes flagged every AI sample at 99%, whether it was an AI academic essay, creative piece, or a LinkedIn post.

False positives on human content: No human sample scored greater than 1%. This means a student submitting original work is highly unlikely to have it flagged as AI before submission.

Mixed content detection: The 90% accuracy rating is the most important result. It detected hand-paraphrased AI content at an accuracy rate of 90%, whereas other applications, such as GPT Zero, Quillbot, and Copyleaks, failed to identify this mixed content.

Notable patterns: Results were consistent across academic, creative, and social writing. For SEO writers, a light rewrite of a ChatGPT draft won’t produce a false all-clear.

Pros

Passed all seven tests, including the mixed sample
Human samples stayed at 1% or lower.
Detection and humanizing in one workflow
Free Chrome extension, API, and MCP access for wider workflows
Free AI Checker also available

Cons

Per-request limits start at 750 words on the Starter plan

Pricing

2. Proofademic: Best AI Detector for Teachers and Academic Work

Proofademic is an AI detector for academic writing built specifically for teachers, professors, and anyone who reviews essays and research papers. It posted the highest mixed score of any ranked tool, 93%, while keeping every human sample at 1% or lower.

For a teacher, those numbers matter much more than the headline claim of accurate detection. It means honest students will rarely be falsely accused, and as long as there has been some rewording, even the most sophisticatedly rewritten AI-generated essay will be detected.