September 2026 review
AI humanizers head to head
Every tool in the panel rewrote the same 50 texts, so these pages can report something a leaderboard cannot: how often each tool bypassed detection on the same input. Two tools can post identical averages and still disagree on half the samples.
| Pairing | Highest bypass rate | Margin | Both passed | Neither passed |
|---|---|---|---|---|
| StealthGPT vs WriteHuman | StealthGPT | 14 to 1 | 31 | 3 |
| StealthGPT vs Grubby | StealthGPT | 29 to 1 | 17 | 3 |
| StealthGPT vs Rephrasy | StealthGPT | 26 to 0 | 20 | 4 |
| StealthGPT vs Undetectable.ai | StealthGPT | 31 to 0 | 15 | 4 |
| StealthGPT vs RewriteAI | StealthGPT | 33 to 0 | 13 | 4 |
| StealthGPT vs HIX Bypass | StealthGPT | 45 to 0 | 1 | 4 |
| StealthGPT vs Humbot | StealthGPT | 46 to 0 | 0 | 4 |
| StealthGPT vs BypassGPT | StealthGPT | 46 to 0 | 0 | 4 |
| StealthGPT vs Ryne | StealthGPT | 46 to 0 | 0 | 4 |
| WriteHuman vs Grubby | WriteHuman | 17 to 2 | 15 | 15 |
| WriteHuman vs Rephrasy | WriteHuman | 14 to 1 | 18 | 16 |
| WriteHuman vs Undetectable.ai | WriteHuman | 18 to 0 | 14 | 17 |
| WriteHuman vs RewriteAI | WriteHuman | 21 to 1 | 11 | 16 |
| WriteHuman vs HIX Bypass | WriteHuman | 31 to 0 | 1 | 17 |
| WriteHuman vs Humbot | WriteHuman | 32 to 0 | 0 | 17 |
| WriteHuman vs BypassGPT | WriteHuman | 32 to 0 | 0 | 17 |
| WriteHuman vs Ryne | WriteHuman | 32 to 0 | 0 | 17 |
| Grubby vs Rephrasy | Rephrasy | 9 to 7 | 11 | 23 |
| Grubby vs Undetectable.ai | Grubby | 9 to 6 | 9 | 26 |
| Grubby vs RewriteAI | Grubby | 10 to 5 | 8 | 27 |
| Grubby vs HIX Bypass | Grubby | 17 to 0 | 1 | 32 |
| Grubby vs Humbot | Grubby | 18 to 0 | 0 | 32 |
| Grubby vs BypassGPT | Grubby | 18 to 0 | 0 | 32 |
| Grubby vs Ryne | Grubby | 18 to 0 | 0 | 32 |
| Rephrasy vs Undetectable.ai | Rephrasy | 9 to 4 | 11 | 26 |
| Rephrasy vs RewriteAI | Rephrasy | 11 to 4 | 9 | 26 |
| Rephrasy vs HIX Bypass | Rephrasy | 19 to 0 | 1 | 30 |
| Rephrasy vs Humbot | Rephrasy | 20 to 0 | 0 | 30 |
| Rephrasy vs BypassGPT | Rephrasy | 20 to 0 | 0 | 30 |
| Rephrasy vs Ryne | Rephrasy | 20 to 0 | 0 | 30 |
| Undetectable.ai vs RewriteAI | Undetectable.ai | 8 to 6 | 7 | 29 |
| Undetectable.ai vs HIX Bypass | Undetectable.ai | 14 to 0 | 1 | 35 |
| Undetectable.ai vs Humbot | Undetectable.ai | 15 to 0 | 0 | 35 |
| Undetectable.ai vs BypassGPT | Undetectable.ai | 15 to 0 | 0 | 35 |
| Undetectable.ai vs Ryne | Undetectable.ai | 15 to 0 | 0 | 35 |
| RewriteAI vs HIX Bypass | RewriteAI | 12 to 0 | 1 | 37 |
| RewriteAI vs Humbot | RewriteAI | 13 to 0 | 0 | 37 |
| RewriteAI vs BypassGPT | RewriteAI | 13 to 0 | 0 | 37 |
| RewriteAI vs Ryne | RewriteAI | 13 to 0 | 0 | 37 |
| HIX Bypass vs Humbot | HIX Bypass | 1 to 0 | 0 | 49 |
| HIX Bypass vs BypassGPT | HIX Bypass | 1 to 0 | 0 | 49 |
| HIX Bypass vs Ryne | HIX Bypass | 1 to 0 | 0 | 49 |
| Humbot vs BypassGPT | Tied | 0 to 0 | 0 | 50 |
| Humbot vs Ryne | Tied | 0 to 0 | 0 | 50 |
| BypassGPT vs Ryne | Tied | 0 to 0 | 0 | 50 |
“Passed” means a strict bypass on all 5 detectors for that text. Per-detector breakdowns, quality comparisons and length discipline are on each page.
All comparisons
StealthGPT vs WriteHuman
StealthGPT cleared all 5 detectors on 45 of 49 shared texts, WriteHuman on 32. Both failed Pangram on 3 of the same texts.
StealthGPT vs Grubby
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, Grubby on 18. Both failed Pangram on 3 of the same texts.
StealthGPT vs Rephrasy
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, Rephrasy on 20. Both failed Pangram on 3 of the same texts.
StealthGPT vs Undetectable.ai
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, Undetectable.ai on 15. Both failed Pangram on 4 of the same texts.
StealthGPT vs RewriteAI
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, RewriteAI on 13. Both failed Pangram on 4 of the same texts.
StealthGPT vs HIX Bypass
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, HIX Bypass on 1. Both failed Pangram on 4 of the same texts.
StealthGPT vs Humbot
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, Humbot on 0. Both failed Pangram on 4 of the same texts.
StealthGPT vs BypassGPT
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 4 of the same texts.
StealthGPT vs Ryne
StealthGPT cleared all 5 detectors on 46 of 50 shared texts, Ryne on 0. Both failed Pangram on 4 of the same texts.
WriteHuman vs Grubby
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, Grubby on 17. Both failed Pangram on 15 of the same texts.
WriteHuman vs Rephrasy
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, Rephrasy on 19. Both failed Pangram on 15 of the same texts.
WriteHuman vs Undetectable.ai
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, Undetectable.ai on 14. Both failed Pangram on 16 of the same texts.
WriteHuman vs RewriteAI
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, RewriteAI on 12. Both failed Pangram on 16 of the same texts.
WriteHuman vs HIX Bypass
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, HIX Bypass on 1. Both failed Pangram on 17 of the same texts.
WriteHuman vs Humbot
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, Humbot on 0. Both failed Pangram on 17 of the same texts.
WriteHuman vs BypassGPT
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, BypassGPT on 0. Both failed Pangram on 17 of the same texts.
WriteHuman vs Ryne
WriteHuman cleared all 5 detectors on 32 of 49 shared texts, Ryne on 0. Both failed Pangram on 15 of the same texts.
Grubby vs Rephrasy
Grubby cleared all 5 detectors on 18 of 50 shared texts, Rephrasy on 20. Both failed Pangram on 23 of the same texts.
Grubby vs Undetectable.ai
Grubby cleared all 5 detectors on 18 of 50 shared texts, Undetectable.ai on 15. Both failed Pangram on 25 of the same texts.
Grubby vs RewriteAI
Grubby cleared all 5 detectors on 18 of 50 shared texts, RewriteAI on 13. Both failed Pangram on 26 of the same texts.
Grubby vs HIX Bypass
Grubby cleared all 5 detectors on 18 of 50 shared texts, HIX Bypass on 1. Both failed Pangram on 32 of the same texts.
Grubby vs Humbot
Grubby cleared all 5 detectors on 18 of 50 shared texts, Humbot on 0. Both failed Pangram on 32 of the same texts.
Grubby vs BypassGPT
Grubby cleared all 5 detectors on 18 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 32 of the same texts.
Grubby vs Ryne
Grubby cleared all 5 detectors on 18 of 50 shared texts, Ryne on 0. Both failed Pangram on 28 of the same texts.
Rephrasy vs Undetectable.ai
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, Undetectable.ai on 15. Both failed Pangram on 22 of the same texts.
Rephrasy vs RewriteAI
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, RewriteAI on 13. Both failed Pangram on 23 of the same texts.
Rephrasy vs HIX Bypass
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, HIX Bypass on 1. Both failed Pangram on 27 of the same texts.
Rephrasy vs Humbot
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, Humbot on 0. Both failed Pangram on 27 of the same texts.
Rephrasy vs BypassGPT
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 27 of the same texts.
Rephrasy vs Ryne
Rephrasy cleared all 5 detectors on 20 of 50 shared texts, Ryne on 0. Both failed Pangram on 25 of the same texts.
Undetectable.ai vs RewriteAI
Undetectable.ai cleared all 5 detectors on 15 of 50 shared texts, RewriteAI on 13. Both failed Pangram on 28 of the same texts.
Undetectable.ai vs HIX Bypass
Undetectable.ai cleared all 5 detectors on 15 of 50 shared texts, HIX Bypass on 1. Both failed Pangram on 34 of the same texts.
Undetectable.ai vs Humbot
Undetectable.ai cleared all 5 detectors on 15 of 50 shared texts, Humbot on 0. Both failed Pangram on 34 of the same texts.
Undetectable.ai vs BypassGPT
Undetectable.ai cleared all 5 detectors on 15 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 34 of the same texts.
Undetectable.ai vs Ryne
Undetectable.ai cleared all 5 detectors on 15 of 50 shared texts, Ryne on 0. Both failed Pangram on 27 of the same texts.
RewriteAI vs HIX Bypass
RewriteAI cleared all 5 detectors on 13 of 50 shared texts, HIX Bypass on 1. Both failed Pangram on 36 of the same texts.
RewriteAI vs Humbot
RewriteAI cleared all 5 detectors on 13 of 50 shared texts, Humbot on 0. Both failed Pangram on 36 of the same texts.
RewriteAI vs BypassGPT
RewriteAI cleared all 5 detectors on 13 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 36 of the same texts.
RewriteAI vs Ryne
RewriteAI cleared all 5 detectors on 13 of 50 shared texts, Ryne on 0. Both failed Pangram on 30 of the same texts.
HIX Bypass vs Humbot
HIX Bypass cleared all 5 detectors on 1 of 50 shared texts, Humbot on 0. Both failed Pangram on 49 of the same texts.
HIX Bypass vs BypassGPT
HIX Bypass cleared all 5 detectors on 1 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 49 of the same texts.
HIX Bypass vs Ryne
HIX Bypass cleared all 5 detectors on 1 of 50 shared texts, Ryne on 0. Both failed Pangram on 39 of the same texts.
Humbot vs BypassGPT
Humbot cleared all 5 detectors on 0 of 50 shared texts, BypassGPT on 0. Both failed Pangram on 50 of the same texts.
Humbot vs Ryne
Humbot cleared all 5 detectors on 0 of 50 shared texts, Ryne on 0. Both failed Pangram on 39 of the same texts.
BypassGPT vs Ryne
BypassGPT cleared all 5 detectors on 0 of 50 shared texts, Ryne on 0. Both failed Pangram on 39 of the same texts.