Checking text uniqueness online: how to find duplicates and compare two texts

The short answer: to check the uniqueness of your text online, paste your text (at least 50 characters) into PromoPilot's Uniqueness Checker, select the language and mode—"Self-Analysis" or "Compare Two Texts"—and click "Check." You'll receive a uniqueness score, repeating phrases of 3-4 words, lexical diversity (TTR), and, in comparison mode, a similarity percentage and common phrases. Important: this isn't an online search for duplicates; your text isn't being copied anywhere. No registration required.

I use this check in two situations: when accepting articles from authors and AI generators, and when comparing two versions of a page. Self-repetitions are immediately visible, and the comparison shows how much of the "new" version really is.

What does the text uniqueness tool check?

The tool works with the text's own statistics—it counts repetitions and similarities, rather than searching for matches in external databases. This provides both a benefit (complete confidentiality) and a limitation on its capabilities.

Russian, Ukrainian, English, and German are supported, with automatic language detection. Text can be pasted or uploaded from a page via a link.

How to check the uniqueness of a text online?

1. Open the uniqueness checker - it works in the browser.
2. Paste the main text (minimum 50 characters) or upload the page in the "Load from URL" tab.
3. Select a language - or leave it at "Auto-detect".
4. Select a mode. "Introspection" is for a single text; comparison mode is for comparing with another text you insert into the second field.
5. Click "Check" to see the score, replay table and TTR.
6. Rewrite the repetitions and check again - the score should increase.

This is what the tool page looks like: a text field, language and mode selection, a "Check" button, and a description of the metrics below.

Free checks for today are counted in the "Usage" section on the left; after registration, the limit triples.

How to read the result and what to correct first?

Numbers without context mean little, so here's how I interpret them in practice.

1. Repeated 4-gram phrases come first. A four-word phrase that appears 3-4 times in a 1,000-word article is almost always a template: "in our online store you," "high-quality services at an affordable price." Reword or delete.
2. Repeated 3-gram phrases with a keyword. If your main search query is among the frequent phrases, it's overspam. Keep it in the title, first paragraph, and a couple of relevant places, and replace the rest with synonyms.
3. TTR. It depends on the length of the text: shorter texts naturally have a higher TTR, so compare texts of similar length. If one article has a noticeably lower TTR than others on the site, it contains a lot of repetition.
4. Similarity between two texts. For two landing pages on the same website, high similarity is a signal that search engines may consider them duplicates. The common phrases the tool displays are a ready-made list of what to rewrite.

A common mistake is chasing "100% uniqueness." Quotes, product names, legal phrases, and terms are all legally repeated. The goal is to make the text useful and free from boilerplate, not to be completely repeatable.

What tasks does uniqueness checking help the most with?

The tool is most useful when you need to quickly compare texts or accept work without sending it to external services. My typical scenarios:

• Acceptance of articles from the author or AI. A one-minute self-analysis reveals whether the text is composed of repetitive phrases. If 4-gram phrases are repeated dozens of times, the article is returned for revision without being read through.
• Two versions of the same page. If you've rewritten a service description, insert the old and new versions into comparison mode. If the similarity remains high, search engines may not notice the update.
• Landing pages for different cities or services. Compare pairs of pages: the common phrases the tool reveals are the blocks that should be customized for each page.
• A competitor's text and yours. If you were inspired by someone else's article, the comparison mode will show you whether your text contains any wording that is too similar.
• Supplier product descriptions. Compare your description with the supplier's original text: if the similarity is high, you have the same product card as all other stores.

Comparison: PromoPilot and its alternatives

The term "uniqueness checking" covers two different tasks: finding repetitions within a text and finding copies online. Tools solve these problems differently.

Conclusion: for drafts, AI-assisted texts, and version comparisons, offline verification is more convenient—it's instant and confidential. If you suspect your text has been stolen or the author copied it from someone else's website, supplement this with an online search for copies.

This tool is one of 87 free SEO tools from PromoPilot. If you're interested in signs of AI in text rather than repetition, see the adjacent article in the series about the AI detector; if you're interested in keyword frequency, see the article about keyword density analysis.

How does uniqueness checking differ from anti-plagiarism?

Classic anti-plagiarism tools compare your text with a huge database of published pages and documents. This tool doesn't do that: the description explicitly states that it only compares texts you provide. Therefore, "high uniqueness" here means "the text has few repetitions and a rich vocabulary," not "this text isn't available online."

This is a conscious compromise. The text isn't sent to external services, and it can be reviewed before publication—for example, a client's manuscript or an article under NDA. And for searching for copies, there are dedicated tools from the table above.

The second limitation is short texts. For a 300-character product description, the duplicate statistics are almost nonexistent, and the rating will be high regardless of the quality. For short texts, comparison mode is more useful: for example, to ensure that the descriptions of two similar products are not identical.

When is a free tool not enough?

A uniqueness check answers the question of "how many repetitions are there in the text?" But it won't tell you why pages aren't ranking, which ones are competing, or where duplicates are hidden on the site. A specialist is needed if:

• There are hundreds of pages on the site, and you suspect duplicates, but don’t know where;
• after changing the author or switching to AI texts, traffic dropped;
• your content is being copied by competitors, and you need to understand how to protect your position;
• It is necessary to build a flow of articles with quality control at every step.

What can I do for your website?

My name is Valeriy Danyuk, I'm a developer and SEO specialist with 12 years of experience and over 200 clients. For me, content is part of my sales system, not a separate service.

SEO, content and promotion

• Turnkey SEO audit: I find duplicates, cannibalization, and weak pages and suggest what to merge and what to rewrite.
• AI-powered SEO blog: AI writes, illustrates, and publishes articles that bring in organic leads.
• Autoblog with AI agents: a human-free editorial team where articles are written and published by AI agents.

Websites and online stores

• How much does a turnkey website cost in 2026? A breakdown of prices and what's included.
• Tilda with a subscription fee or a website with AI —a fair comparison; a website with an AI assistant can be built in minutes on 1001site.

CRM, accounting and automation

• Accounting, bookkeeping, and a store with 30,000 products – a project for a company from the Czech Republic.

All projects are in the portfolio. Send me a link to your website on Telegram —I'll check for duplicates that could hinder ranking.

Result

1. The tool evaluates originality based on self-repetitions and TTR and compares two texts with each other.
2. Start with repeating 4-grams and keyword spamming, then compare similar pages on the site.
3. This isn't a web search for duplicates: for that, use Copyscape, Grammarly, or a phrase search in quotation marks.
4. The goal is useful, template-free text, not "100% uniqueness"; a platform for such content is conveniently located on 1001site.

Check your latest article: find duplicates for free, and if you suspect duplicates throughout the site, write to me on Telegram.

Sources

• PromoPilot's Uniqueness Check tool page — metrics, modes, languages.
• PromoPilot SEO tools wiki - "does not search for copies on the internet" limitation.
• Copyscape is the official page of the service.
• Grammarly is the official Plagiarism Checker page.