Originality.ai: credit-based AI and plagiarism detector where publishers, agencies and SEO teams audit content at scale

Updated on October 13, 2026

Originality.ai is an online AI content detector and plagiarism checker founded by Jon Gillham and launched in late 2022 from Collingwood, Ontario, Canada. The Basic tier costs nothing and grants 3 scans a day, while the Pro plan starts at $14.95/month ($12.95 billed annually). Across 30 supported languages, the company claims 97.8 % accuracy on its multilingual model, a figure independent tests do not always reproduce.

How Originality.ai scans and scores your content

Originality.ai runs on a credit system. One credit covers 100 words for AI detection alone, two credits when plagiarism checking is added. You can paste text, upload a PDF or DOCX, or enter a URL. The report highlights each sentence on a green-to-red scale and returns a global AI probability percentage.

Deep Scan goes further, explaining why specific passages triggered a flag and suggesting edits. AI Allowance lets you set a tolerated AI threshold, handy for teams that accept partially assisted drafts. A Guideline Checker can even compare the text against your house style rules.

Beyond detection, the dashboard bundles a fact and hallucination checker, a grammar fixer, a readability scorer and a Content Quality Score. Agencies running dozens of articles a week get a single place to audit everything before publishing. The Chrome extension brings the same checks into Google Docs, Firefox and Google Classroom.

Accuracy, false positives and where the detector struggles

The company cites peer-reviewed third-party studies and publishes its own accuracy study, claiming 97.8 % accuracy for its multilingual model. Independent evaluations paint a more nuanced picture, with lower results on text deliberately rewritten to evade detection. Originality.ai itself acknowledges that false positives occur, notably on short texts or copy reworked with rewriting tools.

Over-sensitivity is the most common complaint in online discussions about AI content detection. Formal academic prose and technical writing trigger more false alarms than casual blog posts. Originality.ai has acknowledged the issue without publishing an exact false-positive figure. The safest approach remains treating any score as a cue for human review rather than a definitive ruling.

On the competitive front, GPTZero (whose acquisition by Superhuman, formerly Grammarly, was announced in June 2026) positions itself on low false positives while Copyleaks and Winston AI each emphasize different strengths. No single detector dominates every scenario, and running a second tool in parallel remains standard practice among professional editors.

Pricing and credit mechanics

Three tiers cover different scales of use. Basic is free and gives 3 AI-only scans per day (up to 2,000 words, 60 credits daily). Pro costs $14.95/month or $12.95 billed annually ($155.40/year) and includes 2,000 credits, URL scanning, the Chrome extension, team seats and 30-day scan history. Enterprise is $179/month ($136.58 annually) with 15,000 credits, API access, shareable PDF reports, a dedicated customer success manager and support within one hour.

Extra seats run $9.95/month on Pro and $24.95/month on Enterprise. Subscription credits expire at the end of each month, but credits purchased separately in packs stay valid for two years, a useful option for irregular scanning needs. Annual billing saves up to 23 %. Pricing may change at any time, so the official pricing page should always be checked before committing.

Frequently asked questions