Head to head · September 2026 cycle
Phrasly vs StealthGPT
Phrasly finished 2.5 points ahead of StealthGPT in the September 2026 cycle, 67.58 to 65.10, ranking #8 against #9 in a field of 14. Phrasly scored higher on 1 of 5 detectors and 4 of 7 writing categories. StealthGPT came out ahead on academic essay prompts (79.4 vs 64.5), marketing copy prompts (73.1 vs 61.5) and penalties (−5.0 vs −6.0). The bypass-rate gap, 82.1 to 79.6, sits inside both tools' 95% confidence intervals, so treat bypass as a draw.
- Detectors
- 1 – 3 (1 tie)
- Categories
- 4 – 3
- Components
- 3 – 2
Score components
What the overall score is made of: bypass rate weighs 42%, meaning preservation 32%, readability 16%, consistency across categories 10%. Output-quality penalties come off the total. How scoring works →
CIs overlap marks a gap that sits inside both tools' published 95% confidence intervals for that component; it may not survive another cycle.
Detector by detector
Share of each tool's outputs that a detector classified as human-written. StealthGPT took 3 of 5, with 1 tied.
Writing categories
Category score per writing context: bypass credit only for real rewrites, blended with the category's own meaning preservation and readability. Small categories swing; the prompt count is shown on each row. How category scores work →
Head-to-head history
Overall score in every cycle both tools were tested. They have finished ahead 2 times each across 4 shared cycles.
| Cycle | Phrasly | StealthGPT | Margin |
|---|---|---|---|
| September 2026 | 67.58 #8 | 65.10 #9 | ← 2.5 |
| August 2026 | 63.30 #7 | 45.55 #12 | ← 17.8 |
| July 2026 | 61.47 #9 | 61.52 #8 | → 0.1 |
| June 2026 | 71.10 #8 | 71.47 #7 | → 0.4 |
Where each one wins
Every measure above that one tool won outright, largest margin first within each group.
Phrasly
8 wins- Consistency Score 75.0 vs 63.1
- Meaning preservation Score 66.1 vs 59.4
- Bypass rate Score 82.1 vs 79.6
- GPTZero Detector 81.4 vs 77.4
- Application Essay Category 78.1 vs 60.3
- News Article Category 78.3 vs 64.9
- Business Email Category 51.7 vs 42.7
- Discussion Board Category 60.6 vs 60.1
StealthGPT
8 wins- Penalties Score −5.0 vs −6.0
- Readability Score 70.9 vs 65.4
- Originality.ai Detector 89.5 vs 83.4
- Winston AI Detector 66.6 vs 61.6
- ZeroGPT Detector 68.9 vs 68.0
- Academic Essay Category 79.4 vs 64.5
- Marketing Copy Category 73.1 vs 61.5
- Blog Post Category 60.7 vs 57.7
Questions people ask
Is Phrasly better than StealthGPT?
Phrasly finished 2.5 points ahead of StealthGPT in the September 2026 cycle, 67.58 to 65.10, ranking #8 against #9 in a field of 14. Phrasly scored higher on 1 of 5 detectors and 4 of 7 writing categories. Both tools ran the same 33 prompts, scored by the same 5 detectors, under methodology v1.2.0; every input, output and verdict is published.
Which bypasses AI detectors better, Phrasly or StealthGPT?
Phrasly posted the higher bypass rate, 82.1 vs 79.6, and scored higher on 1 of 5 detectors. Phrasly led on GPTZero; StealthGPT led on Originality.ai, Winston AI and ZeroGPT. The overall bypass gap is inside both 95% confidence intervals, so it is not a reliable difference.
Do Phrasly and StealthGPT keep the original meaning?
Phrasly preserved meaning better, 66.1 vs 59.4 on our 0–100 similarity scale, though the confidence intervals overlap. On readability, StealthGPT rated higher, 70.9 vs 65.4. Penalties this cycle: Phrasly −6.0, StealthGPT −5.0.