Alternatives · 2026
Best GPTZero Alternatives in 2026
24 alternatives · 21 with a free plan · Updated
What are the best GPTZero alternatives?
The best GPTZero alternatives for AI API in 2026 are AI Checker Tool (AI content detector, free), ZeroGPT (AI detection tool, freemium) and Originality.ai (AI content detector and plagiarism checker, paid). 21 of the 24 listed alternatives have a free or freemium plan.
Looking for something other than GPTZero? Below are 24 alternatives in AI API, AI Checker and AI Content Detector, all closely matched, ranked by how much they overlap with GPTZero. GPTZero itself is paid. Each entry shows what the tool does, what it shares with GPTZero, its key features and pricing.
What is GPTZero?
GPTZero checks whether text was written by an AI model such as ChatGPT. It is an AI content detector that also covers grammar, plagiarism and citations, depending on the plan you pick. 96. Essential gives you 150,000 words per month with a basic AI scan, grammar check, AI vocabulary check and a Chrome extension.
- Pricing
- Paid
Key features of GPTZero
- AI detector for identifying text generated by AI models like ChatGPT
GPTZero alternatives compared
| Tool | Pricing | Shared with GPTZero | Match |
|---|---|---|---|
| GPTZero | Paid | — | Original |
| AI Checker Tool | Free | AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker | Strong match |
| ZeroGPT | Freemium | AI API, AI Checker, AI Content Detector, AI Detector, AI Grammar Checker, AI Plagiarism Checker | Strong match |
| Originality.ai | Paid | AI API, AI Content Detector, AI Detector, AI Grammar Checker, AI Plagiarism Checker | Strong match |
| SpamCheck.ai | Paid | AI API, AI Checker, AI Content Detector, AI Detector | Strong match |
| SpeedAI | Free | AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker | Strong match |
Top 24 alternatives to GPTZero
- #1
AI Checker Tool is an AI content detector that flags text likely written by models like ChatGPT and also runs plagiarism checks.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker
- Accurately identifies AI-generated content
- Offers plagiarism checking
- Supports multiple AI models like ChatGPT and Google Bard
Pricing: free
- #2
ZeroGPT is an AI detection tool that checks text for AI writing, plus summarizer, paraphraser, grammar and plagiarism checks.
In common with GPTZero: AI API, AI Checker, AI Content Detector, AI Detector, AI Grammar Checker, AI Plagiarism Checker
Pricing: free plan, paid plans from $0.03
- #3
Originality.ai is an AI content detector and plagiarism checker that scans text for AI-generated writing and copied passages.
In common with GPTZero: AI API, AI Content Detector, AI Detector, AI Grammar Checker, AI Plagiarism Checker
- Pay as you go One time on-demand pricing
- Get 3
- Need more? You can buy additional credits as needed under "Settings" in your account
Pricing: paid, from $30
- #4S
AI spam detection API that screens user-generated content for spam before it is posted, with paid plans starting at $9.
In common with GPTZero: AI API, AI Checker, AI Content Detector, AI Detector
- AI-powered spam detection and prevention for user-
Pricing: paid, from $9
- #5
AI humanizer that rewrites text to get past AI detection checks, with a free tier of 500 words and paid plans for students and writers.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker
- Words)
- Try core features for free
- Basic 20
Pricing: free
- #6
Essay Grader AI is an essay grading tool for teachers that gives feedback, summaries, and plagiarism and AI content checks on student writing.
In common with GPTZero: AI Content Detector, AI Grammar Checker, AI Plagiarism Checker
- Dedicated user groups and webinars
- Priority video support
Pricing: free plan, paid plans from $6.99
- #7
Detecting-AI is an AI content detector that flags AI-generated text, with a free plan that allows 100 detections a day.
In common with GPTZero: AI API, AI Checker, AI Content Detector, AI Detector
Pricing: free
- #8
Dechecker is an AI content detector that flags text likely written by ChatGPT, Claude, Gemini and other models, sentence by sentence.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
- Instantly detects AI-generated content from various models (ChatGPT
- GPT-4
- Claude
Pricing: free
- #9
Chrome extension that scans webpages to identify content generated by AI models.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
- Easy to use with Chrome integration
- Detects content from multiple AI models
- Offers both manual and automatic scanning
Pricing: free
- #10A
Identifies whether text was written by AI or humans using advanced analysis algorithms.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
Pricing: free
- #11
Online plagiarism checker and AI content detector that scans submitted text for copied passages and AI-generated writing.
In common with GPTZero: AI API, AI Content Detector, AI Grammar Checker, AI Plagiarism Checker
- Online plagiarism and AI content checker with various text analysis tools
Pricing: paid, from $9.95
- #12
AI writing feedback tool that gives students instant feedback on discussions and essays, and helps educators with grading.
In common with GPTZero: AI Content Detector, AI Grammar Checker, AI Plagiarism Checker
- Enhances critical thinking and writing skills
- Provides instant feedback on discussions and essays
- Streamlines grading for educators
Pricing: free
- #13
Copyleaks is a plagiarism checker and AI content detector that scans text in multiple languages and connects to other platforms through an API.
In common with GPTZero: AI API, AI Content Detector, AI Detector
- Comprehensive detection of plagiarism and AI-generated content
- Support for multiple languages
- Integration with various platforms via API and LMS
Pricing: free
- #14
AI or Not is an AI image and audio detector that checks if content was AI-generated, with API access for fraud and misinformation checks.
In common with GPTZero: AI API, AI Checker, AI Content Detector, AI Detector
- Detects AI-generated content in multiple formats (images
- Helps prevent fraud and misinformation
- Offers API access for integration into existing systems
Pricing: free
- #15
Winston AI is an AI content detector and plagiarism checker that estimates whether text or images were generated by AI.
In common with GPTZero: AI API, AI Content Detector, AI Detector
- Free 2
Pricing: free
- #16
Detects whether text was written by humans or generated by AI models like ChatGPT and GPT-4.
In common with GPTZero: AI Content Detector, AI Detector, AI Plagiarism Checker
- AI text detector for identifying AI-generated content
Pricing: free
- #17
AI security software with LLM firewalls and AI governance tools for controlling how businesses use large language models.
In common with GPTZero: AI API, AI Content Detector, AI Detector, AI Plagiarism Checker
Pricing: free plan, paid plans from $9.99
- #18
Free web-based AI content detector that gives an AI probability percentage and plagiarism check for ChatGPT, Gemini and Claude text.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker
- It uses advanced algorithms and APIs to provide an AI probability score percentage
Pricing: free
- #19
CoverSentry is an AI detector that scans cover letters for AI-written text and gives practical tips before you send them.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
- High accuracy in detecting AI-generated text in cover letters
- Prioritizes user privacy by not storing submitted data
- Provides instant scan results with actionable recommendations
Pricing: free
- #20
Chrome extension that checks whether text was written by GPT-3 and returns a probability score.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
- Easy to use Chrome extension
- Provides a probability score for AI-generated text
- Requires at least 50 characters of text for analysis
Pricing: free
- #21
Evaluates 13 AI content detectors, including Originality.ai, GPTZero and Turnitin, for accuracy in spotting AI-generated text in 2025.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector, AI Plagiarism Checker
- Evaluation of 13 AI detectors for accuracy in identifying AI-generated content in 2025
Pricing: free
- #22
AI rewriter, grammar checker and AI detector that runs as a native Mac and Windows app, working inside any application you already use.
In common with GPTZero: AI Content Detector, AI Detector, AI Grammar Checker, AI Plagiarism Checker
- Outperforms Grammarly and QuillBot in AI detection and writing assistance
- Native app for Mac & Windows
- Offers instant rewrites
Pricing: free
- #23
Analyzes text to determine whether it was written by AI models like ChatGPT, Bard, or GPT-4.
In common with GPTZero: AI Checker, AI Content Detector, AI Detector
- It focuses on analyzing the structure
Pricing: free
- #24
Essayget is an AI essay writer and humanizer that rewrites AI text, adds citations, and offers a free Turnitin AI detection report.
In common with GPTZero: AI Content Detector, AI Detector, AI Plagiarism Checker
- Bypasses top AI detectors
- Provides plagiarism-free content
- Generates accurate citations and reference pages
Pricing: free
How we picked these GPTZero alternatives
We rank tools by how closely they match GPTZero: tools that share more of its categories rank first, then tools whose main category, tags and description overlap with it, then community votes and views. Pricing type and features come from each product's SoftwareVital listing. Admins can pin or remove tools from this list.
Frequently asked questions
What are the best alternatives to GPTZero in 2026?
The closest alternatives to GPTZero are AI Checker Tool, ZeroGPT, Originality.ai, SpamCheck.ai and SpeedAI. They are ranked by how many categories and tags they share with GPTZero and how similar their descriptions are, then by community votes and views on SoftwareVital.
What is the closest alternative to GPTZero?
AI Checker Tool is the closest match because it shares AI Checker, AI Content Detector and AI Detector with GPTZero. It is free.
Are there free alternatives to GPTZero?
Yes. 21 of the 24 alternatives have a free or freemium plan, including AI Checker Tool (free), ZeroGPT (freemium), SpeedAI (free), Essay Grader AI (freemium) and Detecting-AI (free). GPTZero is paid.
Which GPTZero alternatives are paid or enterprise tools?
Originality.ai (paid), SpamCheck.ai (paid) and PlagiarismSearch.com (paid) use paid or enterprise pricing, which usually means more support and admin options for teams.
How does GPTZero compare to AI Checker Tool?
AI Checker Tool overlaps with GPTZero in AI Checker, AI Content Detector and AI Detector. Its listed features include accurately identifies AI-generated content, offers plagiarism checking and supports multiple AI models like ChatGPT and Google Bard. Pricing: free. Open the side-by-side compare page for a full breakdown.
What category is GPTZero in?
GPTZero is listed under AI API on SoftwareVital. Browse that category to see more tools in the same group.