AIDetector
Instantly detect AI-generated text from ChatGPT, GPT-4, Claude, Gemini, and other popular models.
Free plan
No CCAuto-renews
Easy start 2/3Open site
9 Best GPTZero Alternatives in 2026
Looking for alternatives to GPTZero? Below are 9 tools that do a similar job, compared on the details that decide whether you can actually use them: the size of the free allowance, whether a credit card is required, and whether the output is watermarked. GPTZero itself its free tier offers free plan, and we have not confirmed the credit-card requirement.
GPTZero at a glance
Best free AI detector - simply paste your text to instantly get an overall AI score and advanced sentence by sentence de
Free planEasy start 1/3
Read the full GPTZero review →Comparison
Hover over any tool name for its page. Blank cells mean we have not confirmed that detail yet.
| Tool | Free tier | Card | Watermark | From |
|---|---|---|---|---|
| GPTZerothis tool | Yes | — | — | Not published |
| AIDetector | Yes | Not required | — | Not published |
| Isgen | 12000 word a month | — | — | Not published |
| Quetext | Yes | — | — | Not published |
| SuperHumanizer | Yes | — | — | Not published |
| Originality.AI | — | — | — | Not published |
| Scribbr | — | — | — | Not published |
| Undetectable AI | — | — | — | Not published |
| AI or Not | — | — | — | Not published |
| Cara | — | — | — | Not published |
Alternatives in detail
Isgen
Isgen is the leading AI Detector for detecting text written by Openai's GPT-5, Chat-GPT, Claude, Gemini, Deepseek a
12,000 words / month free
Auto-renews
Easy start 1/3Open site
Quetext
Plagiarism Checker and AI Detector by Quetext
Free plan
Auto-renews
Easy start 1/3Open site
SuperHumanizer
Use SuperHumanizer to humanize AI text instantly
Free plan
Auto-renews
Easy start 1/3Open site
Originality.AI
Originality.AI — AI tool
Pricing hidden
Details uncheckedOpen site
Scribbr
Improve your paper with our Proofreading & Editing Service, Plagiarism Checker, Citation Generator, and extensive Kn
Pricing hidden
Details uncheckedOpen site
Undetectable AI
Create with confidence using Undetectable AI's tools
Pricing hidden
Details uncheckedOpen site
AI or Not
AI or Not is the leading AI detector for all content types: text (ChatGPT, Claude), image (Midjourney, 4o), music (Suno,
Pricing hidden
Details uncheckedOpen site
Cara
Cara — AI tool
Pricing hidden
Details uncheckedOpen site
Questions about these alternatives
- Is there a free alternative to GPTZero?
- Yes. 4 of the 9 alternatives listed here have a confirmed free tier. Use the comparison table above to see the exact free allowance for each one.
- Which GPTZero alternatives do not require a credit card?
- 1 alternatives confirm that no credit card is required to start. Check the “Card” column — entries marked “Not required” can be used without payment details.
- What is the best free GPTZero alternative?
- The best free alternative depends on your workflow. The table is sorted by how easy each tool is to start (free tier, no card, no watermark). AIDetector scores 2 out of 3 and is the strongest free option we have verified.
- Can I use GPTZero alternatives for commercial work?
- Some alternatives allow commercial use on their free tier. Look for the watermark and licensing details on each tool's page — we only mark commercial use when the vendor's own terms confirm it.