Originality.ai

Scans text for AI generation and plagiarism before you publish or pay a freelancer for it, with a Chrome extension for Google Docs.

Writing & editing Apps

Checked 25 Sep 2026

Open originality.ai

What you'd use it for

Checking whether a piece of writing was AI-generated or plagiarised before you publish it or pay a freelancer for it.

Score a pasted passage or uploaded file for how likely it is AI-generated, with sentence-level highlighting
Run the same text through a plagiarism check against billions of indexed pages
Scan every page of a domain at once instead of checking articles one by one
Watch a Google Doc as it is written, through the Chrome extension, and flag AI-assisted stretches afterward
Pull a shared scan history and downloadable reports across a team

The verdict

Originality.ai answers one narrow, high-stakes question - did a person write this, or a model - and pairs that score with a plagiarism check, the combination publishers reach for before content goes live under someone else's byline. It performs well against competitors in third-party testing, but even that testing puts real-world accuracy well below the 99%+ figure the vendor advertises, and false positive rates climb on short or translated passages. Treat a score as evidence to weigh rather than a verdict to act on alone, which is the caveat Originality.ai itself gives. It suits a team that regularly buys content from freelancers; it does nothing for your own prose, which is Grammarly's job.

What it costs

Tier	Price	For	Includes
Basic	$0	Trying the AI checker before committing to a subscription.	3 scans a day, capped at 2,000 words per scan, file upload for docx/pdf/doc.
Pro	$12.95/month billed yearly ($155.40/yr), or $14.95/month billed monthly	An individual or small team doing this regularly.	2,000 credits a month (1 credit per 100 words), full site scans, team management, Chrome extension.
Enterprise	$136.58/month billed yearly ($1,638.96/yr), or $179/month billed monthly	Agencies and publishers scanning at volume.	15,000 credits a month, priority support, 365-day scan history, API access.

Read from Originality.ai's own pricing page on 25 Sep 2026. Vendors change prices without notice.

What you need to start

An email address to create an account (no credit card needed for the free scans)
A Pro plan or higher for plagiarism checking, the Chrome extension and full-site scans
A credit card once you move past the free tier

A couple of minutes for a free account and your first scored scan; upgrading to Pro for plagiarism checking and the Chrome extension is a straight checkout that takes about the same.

Your first run Paste text or upload a file and the AI score appears beside it within seconds, a percentage rating with sentence-level highlighting on the flagged sentences. Reliability drops on passages shorter than roughly 50 words.

Where it breaks

Additional team seats are billed separately from the base plan ($8.62–$24.95/month depending on plan and billing cycle), on top of the tier price above.

Browser-based, with a Chrome extension that runs scans directly inside Google Docs and replays the writing process.

First entry in this reference. There is no previous check to compare it against.

When not to use it

Anyone who wants an automated AI-or-not verdict to act on alone - independent testing (RAID, University of Chicago Booth) puts real-world accuracy meaningfully below the vendor's 99%+ claim, with false positive rates that rise on short passages and on text written in another language and then translated or lightly edited; used that way, a score can end a freelancer relationship on a false accusation. It also is not an editor - it audits someone else's writing rather than improving yours.

If you buy content from freelancers, the question this tool answers is blunt: did a person write this, or did a model? Originality.ai runs an AI-detection score alongside a plagiarism check, and the two together are the standard combination publishers reach for when someone else’s writing is entering their site under someone else’s byline.

The free tier is genuinely limited — three scans a day capped at 2,000 words — enough to see how the tool reads, not enough to run an editorial workflow on. The Pro plan is where a small team actually lives: monthly credits that convert to words scanned, full-site scans so you can check a whole domain rather than one file at a time, and the Chrome extension that watches a Google Doc as it’s written rather than only checking the finished draft.

What it doesn’t do is tell you whether the writing is good. Detection scores are a proxy, not a verdict, and the company itself is careful to frame results as evidence to weigh rather than proof to act on unilaterally — worth remembering before you use a score alone to end a freelancer relationship.

Next to Grammarly or a general editor, this is a narrower, single-purpose tool: it doesn’t improve your prose, it audits someone else’s.

Alternatives

Writing & editingApps

Grammarly

An AI writing assistant that lives inside the apps you already type in, correcting and rewriting as you go rather than waiting for you to paste something into a chat box.

Checked 15 Sep 2026