Writing & AI tools / Compare

Originality.ai vs Undetectable AI

Both do 1 of the same writing & AI tools task. Below is what each says about its own limits and pricing, and how each ranks on signals we can measure or quote.

Disclosure: agathox makes some of the tools listed here. They are labelled and scored by the same method as every other tool.

Pricing, limits and privacy

Free tier

A: Free plan at $0 for limited use: 10K words (100 credits, one time; 1 credit = 100 words). The comparison table instead shows 60 credits renewing daily, so the page is inconsistent. No file upload, PDF download, Deep Scan or API.

B: Only a free trial limited to 250 words is described. More use needs a paid plan.

Paid plan

A: In USD: Pro $12.95/month billed yearly ($155.40/year) or $14.95/month billed monthly, 200K words/month. Enterprise $136.58/month billed yearly or $179/month billed monthly, 1.5M words/month. Extra team seats cost more.

B: 10K words per month: $9.99 monthly or $5.00 per month billed yearly ($60 per year). 20K words: $19.00 monthly or $9.50 per month yearly ($114). 35K words: $31.00 monthly or $15.75 per month yearly ($189). 50K words: $42.50 monthly or $21.25 per month yearly. Business pricing is custom.

Signup

A: Not stated clearly. The page offers a Continue for Free option and an FAQ says sign-up is needed for the full suite.

B: Not stated.

Watermark

A: Not stated.

B: Not stated. The pricing page lists a feature called 'Watermark and future proof' without explaining it.

Where files go

A: Privacy policy says submitted text is stored and processed on its servers and its providers' servers in Canada, the US and other places. Some features send text to OpenAI, which may keep logs up to 30 days. Scan history may be used to train models unless you opt out. Retention is as long as reasonably necessary.

B: Privacy notice says data may be transferred, stored and processed in other countries, and kept as long as needed for its purposes. It does not describe how entered text is handled, and its server-location line is incomplete.

From each tool's own pages, checked 2026-11-01. Prices and limits change; check the tool before you rely on them. Sources are listed on each tool's page.

Compare on a task

Neither tool has been hands-on tested on these tasks yet, and we do not guess. Open a task to see both ranked with every other tool.

• AI content detector

• Only Originality.ai: Plagiarism checker
• Only Undetectable AI: Paraphrasing tool

More

• Alternatives to Originality.ai
• Alternatives to Undetectable AI
• All writing & AI tools, ranked
• How we rank

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