The short answer
Originality.ai is good at catching AI text but flags more human writing than most rivals. In Plagino's March 2026 benchmark of 1,000 documents, it caught 95.6% of AI-written documents and wrongly flagged 4.1% of human-written ones. Plagino caught 97.4% with 0.8% false flags; Turnitin caught 98.2% with 1.4%.
How accurate is Originality.ai in independent testing?
We tested Originality.ai in Plagino's benchmark alongside six other detectors. The corpus had 1,000 documents: 500 written by AI (GPT-4o, Claude and Gemini, some lightly edited by a person) and 500 written by people. Every tool saw the same files through its own web app on default settings, in March 2026. A document counted as flagged if the tool flagged it at all.
We report two numbers separately because they describe different mistakes. The detection rate is the share of AI-written documents a tool caught. The false-positive rate is the share of human-written documents it wrongly called AI. For a student or a teacher deciding whether to act on a flag, the second number matters more.
| Detector | AI documents caught | 95% interval | Human documents wrongly flagged | 95% interval |
|---|---|---|---|---|
| Turnitin (reference) | 98.2% | 96.6–99.1% | 1.4% | 0.7–2.9% |
| Plagino | 97.4% | 95.6–98.5% | 0.8% | 0.3–2.0% |
| Originality.ai | 95.6% | 93.4–97.1% | 4.1% | 2.7–6.2% |
Originality.ai is a strong detector. Its 95.6% detection rate was third of seven, and its interval overlaps with Plagino's, so on this sample we cannot say Plagino catches more AI writing. Turnitin led on detection, ahead of both.
False positives are where Originality.ai fell behind. It wrongly flagged 4.1% of human-written documents, about 1 in 24. That is roughly five times Plagino's 0.8% and three times Turnitin's 1.4%, and its interval does not overlap with Plagino's. In a class of 100 honest essays, a rate like that would put about four students under suspicion.
What does Originality.ai say about its own accuracy?
Originality.ai keeps a detailed accuracy and model history page. It changed its detector substantially in 2026. In July 2026 it launched "AI Allowance", where you choose how much AI to allow in a document (0%, 5%, 15%, 25% or 40%). In September 2026 it retired its classic Lite, Turbo and Academic models.
On its own V6 benchmark, Originality.ai reports 99.4% overall accuracy and 98.5% precision for AI Allowance at the default 15% threshold. At 5%, it reports 98.0% accuracy and 91.1% precision, which it describes as "highly sensitive". For the retired models, it previously reported a 0.5% false positive rate for Lite 1.0.2 and 1.5% for Turbo 3.0.2, both from September 2025.
Why our false-positive rate is higher than Originality.ai's
Our measured 4.1% is well above the vendor's published false-positive figures. Some of the gap is normal: vendors test on their own datasets, while an outside test uses documents the vendor has never seen. Independent research shows how much results move with the test set. The RAID benchmark, published at ACL 2024, found that Originality's accuracy at a fixed 5% false-positive rate ranged from 51.2% to 99.9% depending on which model wrote the text and how it was generated.
Some of the gap may also be timing. We tested in March 2026, before AI Allowance launched, using whatever default model the web app ran then. The current detector is different, and a re-run could produce different numbers in either direction. We will re-test Originality.ai in the next quarterly benchmark and update this page.
What does Originality.ai cost and what does it check against?
Originality.ai bundles AI detection, plagiarism checking, readability, grammar and fact-checking into its paid plans. The figures below come from the Originality.ai pricing page and its plagiarism checker page, checked in October 2026. Prices are in US dollars and change often, so confirm them before you subscribe.
| Originality.ai | Plagino | |
|---|---|---|
| Free use | Basic: AI detection only, 3 scans a day, up to 2,000 words per scan | 3 scans per month, no card |
| Entry paid plan | Pro: $14.95/month, or $12.95/month billed annually ($155.40/year) | Pro: $19/month |
| Usage on that plan | 2,000 credits a month; 1 credit covers 100 words; unused credits expire at month end | 20 scans per day |
| Higher plan | Enterprise: $179/month, or $136.58/month billed annually; 15,000 credits a month, API access and 365-day scan history | None |
| Teams | Extra seats: $9.95/month on Pro ($8.62 billed annually) | Team: custom pricing for departments and writing centres |
| Plagiarism check compares against | Web app: public web content via Google search. LMS and institutional integrations add academic journal databases and a private repository | Open-access academic literature via CORE only |
| Other checks | Readability, grammar, fact-checking, full website scans | None |
| How you submit | Paste, .docx, .doc or PDF upload, URL, Chrome extension, Google Docs, Moodle plugin | .docx upload in the web app |
| Report | AI score; shareable and downloadable reports | PDF with sentence-level AI highlights and matched sources |
The source lists differ sharply. Originality.ai's web app searches the public web, which Plagino does not. Plagino's plagiarism checker matches against open-access research through CORE, and every match points at the exact overlapping words. Neither tool can see Turnitin's private repository of student papers.
What does Originality.ai do with your text?
The Originality.ai privacy policy says that, unless you opt out, it may use your scan history and scan results to help train and improve its models. It states that all users can opt out of this. It also says it does not use personal data or student data to train AI or large language models.
Schools get stronger terms. Where a school has an official institutional agreement with Originality.ai, the policy says student data is used only to provide and improve the contracted service and is not used to train general-purpose AI models. A student using a personal account is not covered by that agreement, so check the opt-out setting if it matters to you.
Where Originality.ai is the better choice
Originality.ai is built for publishers, agencies and content teams, and for that work it does more than Plagino does.
Publishers checking web content
If you edit freelance articles or run a website, Originality.ai fits better. It scans whole websites by URL, checks plagiarism against the public web, and adds fact-checking, readability and grammar in one plan. Its Chrome extension can also replay how a Google Doc was typed, which gives an editor more context than a score alone. Plagino does none of this.
Heavy use at a low price, and flexible thresholds
At $12.95 a month billed annually for 2,000 credits, about 200,000 words, Originality.ai is priced for bulk checking by word count, and its free tier allows 3 AI scans a day. The AI Allowance setting also lets you choose how much AI assistance to tolerate, which suits teams with a written AI policy. Schools on Moodle get a plugin; Plagino has no LMS integration.
Where Plagino is the better choice
Plagino is our tool, so read this with that in mind. The clearest difference in our benchmark was false positives: Plagino wrongly flagged 0.8% of human-written documents against Originality.ai's 4.1%, and that gap is outside the margin of error. If you are a student checking your own essay, or a teacher who wants to avoid accusing an honest writer, a lower false-positive rate is the number to prioritise. Plagino also caught slightly more AI writing (97.4% against 95.6%), though that difference is within the margin.
Plagino is built for academic drafts. You upload a .docx file and get a PDF report with sentence-level AI-writing highlights and matched academic sources, which you can keep and discuss with a tutor. The free plan gives 3 scans a month with no card, and Pro costs $19 a month for 20 scans a day.
Whichever tool you use, a score is a signal, not proof. If a detector has flagged your work, our guide for students falsely accused of using AI explains how to respond through your institution's process.
Test conditions and limitations
These limits apply to Plagino's results as much as to Originality.ai's.
What the benchmark does not cover
The corpus was English only and the AI documents came from GPT-4o, Claude and Gemini, so results on other languages or newer models may differ. We scored at document level, so one flagged sentence in a human essay counted as a false positive. We used each tool's default settings in March 2026; Originality.ai's AI Allowance, which lets you raise the threshold to reduce false positives, did not exist yet.
Each rate rests on 500 documents. That separates large gaps, such as the false-positive difference between Originality.ai and Plagino, but not small ones, such as their detection rates. The confidence intervals in the first table show which is which.
Who gets falsely flagged
A single rate also hides who bears the errors. A 2023 Stanford study found that several AI detectors misclassified more than half of TOEFL essays by non-native English writers as AI-generated. Turnitin reports that false positives are more common in documents with less than 20% AI writing. Our guide to AI detector false positives covers what to do with a borderline result.
For other head-to-head results, see Plagino vs Copyleaks, Plagino vs Winston AI and Plagino vs Scribbr.
Frequently asked questions
Is Originality AI accurate?
It catches AI writing well but produces more false positives than most rivals. In Plagino's March 2026 benchmark of 1,000 documents, Originality.ai caught 95.6% of AI-written documents and wrongly flagged 4.1% of human-written ones. Originality.ai's own benchmark reports 99.4% accuracy for its AI Allowance detector at the default 15% threshold.
Does Originality AI give false positives?
Yes. It wrongly flagged 4.1% of human-written documents in Plagino's benchmark, the third-highest rate of seven detectors tested. Originality.ai publishes its own false-positive figures and offers AI Allowance thresholds that trade detection for fewer false flags. Treat any flag as a reason to review drafts, not as proof.
Is Originality AI free?
There is a free Basic plan for AI detection only, with 3 scans a day and up to 2,000 words per scan. Plagiarism checking, readability and fact-checking need a paid plan, which starts at $14.95 a month, or $12.95 a month billed annually, for 2,000 credits.
Is Originality AI better than Turnitin?
Not in Plagino's benchmark. Turnitin caught 98.2% of AI-written documents against 95.6% for Originality.ai, and wrongly flagged 1.4% of human documents against 4.1%. Turnitin is only sold to institutions, though, while anyone can buy Originality.ai.
Does Originality AI use my text to train its models?
It may. Originality.ai's privacy policy says scan history and results may be used to train and improve its models unless you opt out, and that all users can opt out. Student data processed under an official school agreement is not used to train general-purpose AI models.
Who is Originality AI designed for?
Mainly publishers, agencies and content teams. It scans websites, checks plagiarism against the public web and adds fact-checking and readability. It also offers a Moodle plugin and enterprise plans for schools and agencies, but its feature set is built around web content.