Offers broad multilingual AI detection and text humanization, but lacks GPTZero's detailed deep-scan reporting features.
GPTZero records 23,246,989 monthly visits with +32.5% month-over-month growth and Freemium, Paid pricing. ProofUp records 0 monthly visits with -100% growth and Contact for Pricing pricing.

Verify income, identity, and documents before you hand over the keys
| Dimension / Metric | ![]() | |
|---|---|---|
| Official Domain | gptzero.me | proofup.com |
| Pricing Model | Freemium, Paid | Contact for Pricing |
| Monthly Visits | 23.25M (23,246,989) | 0 (0) |
| MoM Traffic Delta | +5.7M (+32.5%) |
| -1.73K (-100%) |
| Primary Market & Share | 🇺🇸 United States (54%) | 🌐 Global (—) |
|---|
| Direct Visits / mo | 7.53M | 0 |
|---|
| User Rating | 4.1 | 4 |
|---|
| Supported Platforms | Website | Website |
|---|
AI detection and writing verification built for schools and editors
Paste text or upload a document and get an overall AI probability score plus a sentence-by-sentence breakdown of which parts look machine-written.
Flags AI text from major model families including ChatGPT, Gemini, Claude, Llama, and others, rather than training for a single model.
A Chrome extension and Google Docs add-on bring scanning into Gmail, Docs, Classroom, and other surfaces you already work in.
Checks content for copied passages from outside sources so you can separate AI-generation questions from originality questions.

Verify income, identity, and documents before you hand over the keys
Applicants connect bank and payroll accounts through Plaid so earnings are read from the account itself, with no document in the path to forge. Uploaded documents are also analyzed for deposit frequency and real income.
A government ID photographed front and back is matched against a live selfie using facial recognition, catching borrowed identities before keys are handed over.
Uploaded PDFs are read at the byte level for hidden text layers, metadata mismatches, generator fingerprints, and post-generation edits — evidence that visual inspection misses.
Each application returns one of five verdicts (pass, pass with caution, non-recurring, needs review, fail) with a risk level and the specific signals that produced it.
Offers broad multilingual AI detection and text humanization, but lacks GPTZero's detailed deep-scan reporting features.

SpecialistCombines AI detection with professional human proofreading and citation tools, but functions primarily as an editing service.
#2Free / Open-sourceDetect, humanize and verify AI content in one place

Enterprise AI and plagiarism detection for content integrity

Delivers strong fact-checking and comprehensive site-wide plagiarism audits, but has stricter paywalls than GPTZero.

Provides detailed sentence-level analysis for multilingual text, but lacks GPTZero's broad academic brand recognition.

Free / Open-sourceDetect AI-generated text and images with benchmark-tested accuracy
AI detector that highlights evidence, not just a score

SpecialistTailors detection specifically for academic institutions and LMS integrations, but is less optimized for casual web users.

SpecialistHumanize AI text and check it against AI detectors

SpecialistCheck plagiarism, detect AI text and polish your writing in one place

Free AI content detector that flags machine-written text and helps you rewrite it
Offers broad multilingual AI detection and text humanization, but lacks GPTZero's detailed deep-scan reporting features.
SpecialistCombines AI detection with professional human proofreading and citation tools, but functions primarily as an editing service.
Free / Open-sourceDetect, humanize and verify AI content in one place
Delivers strong fact-checking and comprehensive site-wide plagiarism audits, but has stricter paywalls than GPTZero.
Provides detailed sentence-level analysis for multilingual text, but lacks GPTZero's broad academic brand recognition.
Free / Open-sourceDetect AI-generated text and images with benchmark-tested accuracy
AI detector that highlights evidence, not just a score
SpecialistTailors detection specifically for academic institutions and LMS integrations, but is less optimized for casual web users.
SpecialistHumanize AI text and check it against AI detectors
SpecialistCheck plagiarism, detect AI text and polish your writing in one place
Free AI content detector that flags machine-written text and helps you rewrite it