Head to head · September 2026 cycle
Grammarly vs Penlify
Grammarly finished 23.8 points ahead of Penlify in the September 2026 cycle, 60.35 to 36.57, ranking #12 against #14 in a field of 14. Grammarly scored higher on 5 of 5 detectors and 7 of 7 writing categories. Penlify came out ahead on consistency across categories (100.0 vs 78.7) and readability (71.8 vs 66.1).
- Detectors
- 5 – 0
- Categories
- 7 – 0
- 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 →
Detector by detector
Share of each tool's outputs that a detector classified as human-written. Grammarly took 5 of 5.
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 →
Where each one wins
Every measure above that one tool won outright, largest margin first within each group.
Grammarly
15 wins- Bypass rate Score 41.1 vs 0.0
- Meaning preservation Score 86.4 vs 62.7
- Penalties Score −3.0 vs −5.0
- Copyleaks Detector 60.3 vs 0.0
- Originality.ai Detector 43.4 vs 0.0
- Winston AI Detector 38.9 vs 0.4
- GPTZero Detector 15.9 vs 0.0
- ZeroGPT Detector 58.0 vs 43.0
- Academic Essay Category 69.5 vs 27.0
- News Article Category 62.8 vs 36.6
- and 5 more
Penlify
2 wins- Consistency Score 100.0 vs 78.7
- Readability Score 71.8 vs 66.1
Questions people ask
Is Grammarly better than Penlify?
Grammarly finished 23.8 points ahead of Penlify in the September 2026 cycle, 60.35 to 36.57, ranking #12 against #14 in a field of 14. Grammarly scored higher on 5 of 5 detectors and 7 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, Grammarly or Penlify?
Grammarly posted the higher bypass rate, 41.1 vs 0.0, and scored higher on 5 of 5 detectors. Grammarly led on GPTZero, Originality.ai, Copyleaks, Winston AI and ZeroGPT.
Do Grammarly and Penlify keep the original meaning?
Grammarly preserved meaning better, 86.4 vs 62.7 on our 0–100 similarity scale. On readability, Penlify rated higher, 71.8 vs 66.1. Penalties this cycle: Grammarly −3.0, Penlify −5.0.