Skip to content



Head-to-head comparison

Undetectable AI vs GPTHumanizer

Tested side by side with the same prompts, same detectors, same scoring. Here is how they compare on bypass rate, meaning preservation, readability, pricing, and which writer each tool actually suits best.

Last tested: Jun 2, 2026
Sample size: 30
Methodology
5 detectors
Winner

Undetectable AI

undetectable.ai
80.09
Overall Score
94.1%Bypass
72.2Meaning
100Readability

Runner-up

GPTHumanizer

gpthumanizer.com
65.82
Overall Score
68.4%Bypass
70.1Meaning
100Readability

Side-by-side scores

Both tools were tested with 30 identical prompts across 6 writing categories (academic essays, blog posts, marketing copy, news articles, application essays, discussion posts). Each output was scored by 5 independent AI detectors. Here is how the numbers compare:

Overall
80.09

Undetectable AI

65.82

GPTHumanizer

Bypass Rate
94.1%

Undetectable AI

68.4%

GPTHumanizer

Meaning
72.2

Undetectable AI

70.1

GPTHumanizer

Readability
100

Undetectable AI

100

GPTHumanizer

Penalties
-8

Undetectable AI

-3

GPTHumanizer

Metric Undetectable AI GPTHumanizer Winner
Overall Score 80.09 65.82 Undetectable AI
Bypass Rate 94.1% 68.4% Undetectable AI
Meaning Preservation 72.2 70.1 Undetectable AI
Readability 100 100 Tie
Penalties -8 (length inflation) -3 (minor meaning drift) GPTHumanizer

Detector-by-detector results

Not all detectors work the same way. Here is how each tool performed against each of the 5 detectors we tested. The tool with the higher bypass score on each detector is highlighted.

GPTZero
Undetectable AI

95.1

GPTHumanizer

71.3

Winston AI
Undetectable AI

96.7

GPTHumanizer

70.2

ZeroGPT
Undetectable AI

78.3

GPTHumanizer

65.8

Copyleaks
Undetectable AI

74.6

GPTHumanizer

67.4

Originality.ai
Undetectable AI

66.3

GPTHumanizer

62.1

Undetectable AI wins on 5 of 5 detectors. GPTHumanizer wins on 0.

Our verdict

Editor’s assessment

Undetectable AI is the stronger overall performer in this matchup. Its bypass rate (94.1%) is higher than GPTHumanizer’s (68.4%), and it wins against 5 of the 5 detectors where there is a clear winner. The 8-point penalty for length inflation is a real issue, but even with that hit, Undetectable AI still finishes 14.3 points ahead on overall score.

GPTHumanizer is not a bad tool.

For most use cases, Undetectable AI is the better pick.

Pricing comparison

Price alone should not drive the decision, but it is worth knowing what you are paying for. Here is how these two compare on the entry-level monthly plan:

Undetectable AI
$19 /mo

Free tier available

GPTHumanizer
$9.99 /mo

Free tier available

GPTHumanizer is 47% cheaper at $9.99/mo vs $19/mo. Both offer a free tier to test before committing.

Who should pick which

Different tools suit different workflows. Here is a practical breakdown of when each tool is the better fit:

Pick Undetectable AI if…

  • You want the higher overall score and broader detector coverage
  • Raw bypass rate is your top priority (94.1% vs 68.4%)
  • Meaning preservation matters to your workflow
  • GPTZero is your primary detection concern (95.1 vs 71.3)
  • Winston AI is your primary detection concern (96.7 vs 70.2)

Pick GPTHumanizer if…

  • Budget matters and you prefer the lower-priced option ($9.99/mo vs $19/mo)
  • You want fewer quality penalties and cleaner output
  • You have tested it yourself and prefer its specific output style

Frequently asked questions

Is Undetectable AI better than GPTHumanizer?

In our independent testing across 5 AI detectors, Undetectable AI scored 80.09 overall compared to GPTHumanizer at 65.82. Undetectable AI wins on raw bypass rate (94.1% vs 68.4%) and leads on 5 of 5 detectors. The better choice depends on which specific detectors matter most to your workflow.

Which is cheaper, Undetectable AI or GPTHumanizer?

Undetectable AI starts at $19/month with a free tier. GPTHumanizer starts at $9.99/month with a free tier.

Which AI humanizer is best for bypassing Turnitin?

Between these two tools, Undetectable AI performs better against Originality.ai (which Turnitin’s detection is based on), scoring 66.3 compared to 62.1. If Turnitin specifically is your concern, Undetectable AI has the edge in this matchup.

How were these AI humanizers tested?

We tested both tools using identical prompts across 6 writing categories (academic essays, blog posts, marketing copy, news articles, application essays, discussion posts), then ran every output through 5 independent AI detectors. Our full methodology is published at aihumanizertools.com/how-we-test-ai-humanizers/.

Next move

Use this comparison alongside the full reviews and our testing methodology before making a subscription decision.

Looking for the best AI humanizer? We tested 16 tools head-to-head. See our full Best AI Humanizer in 2026 ranking with bypass rates, pricing, and detailed reviews.