ZeroGPT is a web-based AI detector that comes with writing tools, including a paraphraser and a basic AI humanizer.1 HumanGPT is an iPhone app that rewrites AI drafts so they sound like you and shows an AI-likeness estimate for every sentence. Below, every claim about ZeroGPT links to a source.
ZeroGPT is built around its detector. HumanGPT is built around rewriting, with an AI-likeness estimate as a check.
Small numbers link to the sources at the end of the page.
| Feature | HumanGPT | ZeroGPT |
|---|---|---|
| Platforms | iPhone app (iOS 17 or later). Web editor planned, not live yet. | Web app and API. Paid plans add access through WhatsApp and Telegram.2 |
| Free plan | Yes 1 free demo rewrite, then 300 words a day, up to 300 words per rewrite. | Yes No credit card. Detector 15,000 characters per check, paraphraser 300 words, Basic Humanizer, ads.23 |
| Paid pricing | Pro: $5.99 a week with a 3-day free trial, or $39.99 a year (US prices).7 | From €14.99 a month, or €8.99 a month billed annually (as shown in Germany).2 |
| Word limits | Free: 300 words a day. Pro: 50,000 words a week (fair use), up to 3,000 words per rewrite. | Detector: 15,000 characters per check free, 100,000 to 150,000 on personal plans. Paraphraser: 300 words per check, 5,000 on MAX.2 The humanizer FAQ says the free humanizer works "without limits or registration".3 |
| Rewriting approach | Anthropic Claude models and the open-source humanizer skill (26 patterns from Wikipedia's "Signs of AI writing"). Tones, strength, text types; voice matching and sentence rewrite on Pro. | "Humanize Text" with a Basic model, plus an Advanced model the page says is "provided by Undetectable AI". Paraphraser with tone and mode settings.34 |
| AI-likeness or detection | Yes AI-likeness estimate with per-sentence highlights. An estimate, not proof. | Yes Sentence highlights and a percentage gauge. PDF reports and batch uploads on paid plans.12 |
| Facts and citations kept | Yes Integrity check for facts, numbers and citations, plus a fact-check pass when needed. | Not stated The FAQ advises: "Use the AI Paraphraser, then verify facts."5 |
| Document import and export | Import .txt, photos and scans (on-device OCR), Google Docs and web links; PDF and Word on Pro. Export .txt, .docx, .pdf. | Upload .txt, .docx or text-based PDF (OCR scans first). PDF reports on paid plans.25 |
| Languages | App in English, German, Spanish and French. | Website in six languages. The FAQ says "All available languages are supported across all the tools."15 |
| Privacy and data retention | Processed in the EU (Firebase europe-west1) and by Replicate (Anthropic Claude) only to produce results. Results kept 30 days; uploads deleted after extraction. No ads.8 | Olive Works LLC (Wyoming, US). No AI training on private content. Unsaved content kept "for the period reasonably necessary"; may be processed in the US, Germany, the EEA and elsewhere.6 |
| Notable claims | Doesn't promise undetectable text or a pass on any detector or exam. | Advertises "98.4% Detection accuracy". The humanizer page lists a "99% Score as Human Rate" for the Advanced model. We haven't tested these claims.13 |
If one of these is what you need, ZeroGPT fits better:
The free plan checks up to 15,000 characters per scan, with 1,250,000 words a month and no credit card.2 HumanGPT is built for rewriting, and its free plan covers 300 words a day.
ZeroGPT works on the web, with its site in six languages.1 Its paid plans also list WhatsApp and Telegram access.2 HumanGPT is an iPhone app in four languages, and its web editor isn't live yet.
ZeroGPT also has a plagiarism checker, summarizer, grammar checker, translator and AI image and video detectors.1 Paid plans check 50 or more files in a batch, and there are EDU and enterprise plans. The MAX paraphraser takes 5,000 words per check; HumanGPT Pro takes 3,000 per rewrite.2
ZeroGPT's sources don't describe these features, or describe them differently.
Pick a tone (natural, casual, professional, academic or friendly), a strength and a text type. On Pro, match your own voice from a writing sample, or rewrite only the sentences the AI-likeness estimate marks.
Every rewrite gets an integrity check for facts, numbers and citations. When your text has numbers, names or citations, or something looks changed, a fact-check pass compares the rewrite with your original and fixes what it finds; anything still missing is flagged.
Scan a page with on-device OCR, or import a Google Doc or web link. Pro adds PDF and Word. Export to .txt, .docx or .pdf.
HumanGPT rewrites with Anthropic Claude models, guided by the open-source humanizer skill and its 26 patterns from Wikipedia's "Signs of AI writing".910 It then checks that facts, numbers and citations made it through.
ZeroGPT's steps for its free Basic Humanizer are "Check for AI", then "Humanize Text". The page says detectors "might still flag your text with the Basic Public Model" and links its Advanced model to Undetectable AI's site.3
Customer feedback plays a crucial role in product development. Additionally, it is important to note that teams who reviewed support tickets weekly shipped fixes 30% faster (Nguyen, 2024), showcasing the profound value of listening to users.
Product teams rely on customer feedback. Teams that read their support tickets every week shipped fixes 30% faster (Nguyen, 2024).
Sample text and rewrite written for this page to show typical edits. Results depend on your text and settings. We don't show ZeroGPT output, because one sample can't fairly represent another tool.
ZeroGPT bills monthly or annually, and its plans bundle the detector with other tools.2 HumanGPT Pro is weekly or yearly.
US prices.7
PLUS: €21.99 a month. API humanizer: $0.25 per 1,000 words.2
HumanGPT prices are US prices; ZeroGPT's are in euros as shown in Germany on October 8, 2026. Prices vary by country, and either provider can change them at any time.
For rewriting, it can be. ZeroGPT is mainly an AI detector, with a basic humanizer among its other tools. HumanGPT is an iPhone app built for rewriting, with fact and citation checks and an AI-likeness estimate for every sentence. If you mostly need a free detector in a desktop browser, ZeroGPT suits that job better.
No. No tool can promise how a detector, a teacher or an editor will judge a text, and HumanGPT doesn't try to. It rewrites your draft so it reads naturally and shows an AI-likeness estimate, which is an estimate and not a verdict. Follow the rules of your school or workplace.
ZeroGPT has a free plan, and its personal plans start at €14.99 a month, or €8.99 a month billed annually, as shown in Germany. HumanGPT is free for 300 words a day, and Pro costs $5.99 a week with a 3-day free trial or $39.99 a year in the US. Prices change, so check both before you buy.
Not yet. HumanGPT is an iPhone app for iOS 17 or later, and there's no Android app. A web editor is planned but not available yet.
All sources were last checked in October 2026.
Paste a paragraph, pick a tone and check the AI-likeness estimate. Your first rewrite is free.
For iPhone with iOS 17 or later.