| Undetectable AI | Walter Writes AI | |
|---|---|---|
| Starting price | $9.99/mo | $9/mo |
| Free tier | 250 words | 200 words |
| Bundled detector | Yes | No |
| Founded | 2022 | 2023 |
| Best for | Teams that want one tool to both check and rewrite content across multiple AI models. | Users who process the same type of document repeatedly and want predictable results every time. |
Price: Walter Writes AI is cheaper to start, at $9/mo vs $9.99/mo.
Undetectable AI: $9.99/mo for the entry tier; higher tiers scale by word volume.
Walter Writes AI: Plans from roughly $9/mo depending on monthly word allowance.
Free tier: Undetectable AI offers a more generous free tier (250 words).
If you just want to test either tool before paying, Undetectable AI's 250-word allowance gives you more room to evaluate quality.
Detection performance
Undetectable AI: Frequently cited as a top-tier performer against GPTZero and Originality.ai, though results vary by source text length and topic.
Walter Writes AI: Cited in multiple 2026 comparisons as one of the more reliable mid-tier tools against GPTZero.
AI detector included: Undetectable AI bundles a built-in detector; Walter Writes AI does not.
Strengths at a glance
Undetectable AI
- Runs output against multiple detector models before returning it
- Supports long-document processing without manual chunking
- Adjustable readability and purpose settings (story, essay, article, email)
Walter Writes AI
- Reliable, repeatable output across multiple passes on the same document
- Praised in independent tests for maintaining natural sentence flow
- Simple flat pricing without confusing tiers
Our verdict
Choose Undetectable AI if: teams that want one tool to both check and rewrite content across multiple ai models. Choose Walter Writes AI if: users who process the same type of document repeatedly and want predictable results every time.
Full Undetectable AI review → · Full Walter Writes AI review →