Free Plagiarism Checker

You’re working on a paper, and you’ve just written a line that seems kind of familiar. Did you read it somewhere while you were researching the topic? If you did, does that count as plagiarism? Now that you’re looking at it, there are a couple of other lines you borrowed from somewhere. You didn’t bother with a citation when writing because you didn’t plan to keep those lines. But now they’re an important part of your paper. Is it still plagiarism if they make up less than a paragraph?

Using someone else’s text without attribution is plagiarism, whether you mean to do it or not. In fact, a writer can even commit plagiarism by using their own work without proper citation.

Unintentional plagiarism of even a sentence or two can have serious consequences. For students, plagiarism often means a failing grade, academic probation, or worse. Fortunately, it’s easy to ensure the authenticity of your work by using a plagiarism checker. Doing so will help you spot any unintentional use of others' words or ideas and prevent academic consequences in the future.

You might be surprised to learn there are seven types of plagiarism:

1. Complete plagiarism is an overt form of plagiarism. This happens when you present someone else’s work as your own, such as buying an essay or using another’s work without credit.

2. Direct plagiarism is copying sections of another’s work without crediting the author rather than copying the entire piece like complete plagiarism.

3. Paraphrasing plagiarism is rewording someone else's work without credit. Even if the ideas aren’t in the original words, this form of paraphrasing is still plagiarism.

4. Self-plagiarism is reusing your own previous work in a new context. Even if it’s your original thought, this can be considered plagiarism.

5. Patchwork plagiarism, also known as mosaic plagiarism, involves integrating plagiarized material with your own work, often subtly.

6. Source-based plagiarism consists of citing sources in a misleading way. For instance, a writer may refer to a secondary source in their work but only cite the primary source from which the secondary source was taken. This form of plagiarism can also include making up sources or citing incorrect sources.

7. Accidental plagiarism, as the name suggests, happens when the author plagiarizes content unintentionally. It can include failing to cite sources, not putting quotes around cited material, and making mistakes when citing sources. Despite being accidental, this type of plagiarism still carries serious consequences.

8. AI plagiarism is using writing created with generative AI without disclosing its origin. When you use gen AI to write, summarize, or paraphrase, you need to include a citation.

Understanding the various forms of plagiarism is the first step in preventing it. Next, it’s critical to cite your sources and credit the original author or generative AI (yes, gen AI is a source) when using work or an idea that isn’t your own.

As a final step, you can use a free plagiarism detector or plagiarism remover to check for copyright infringement. Grammarly’s online plagiarism checker can help ensure you correctly identified and cited anything in your text that isn’t 100 percent unique. It can also help you properly disclose and cite the use of AI in your writing.

Grammarly’s online plagiarism checker is designed for academia, but it’s a valuable tool for anyone wanting to create original, plagiarism-free work. Whether you’re a student writing an essay, a teacher grading papers, or a writer working on original content for the web, Grammarly’s plagiarism detector will save you time and help you avoid writing mistakes.

While you can check citations and references manually, this may take a very long time. You also risk missing an instance of plagiarism that an instructor could later detect.

To be 100 percent confident when submitting your work, find the best plagiarism checker for your needs and incorporate it into your writing and editing process to check for plagiarism quickly and easily.

Grammarly’s plagiarism checker can quickly detect plagiarism from billions of web pages and from ProQuest’s academic databases. Grammarly will check for originality in your text and tell you whether or not there is any duplicate content. Our Premium plagiarism check feature highlights passages that require citations, allowing you to remove plagiarism and cite your sources easily.

It’s always an excellent idea to learn citation fundamentals and familiarize yourself with your style guide’s correct citation format, whether that’s APA, MLA, or Chicago.

Citing sources can be tedious work, though, and it’s easy to make mistakes. You can save valuable time by using Grammarly Free’s auto-citations feature, which instantly creates citations from millions of articles across 20+ popular research databases and websites, such as Wikipedia, Frontiers, PLOS One, ScienceDirect, SAGE Journals, PubMed, Elsevier, DOAJ, arXiv, and Springer.

You can even double-check any existing citations with Grammarly Premium’s citation style formatting, which catches parentheses, periods, and other punctuation that’s not following your preferred style guide.

An online plagiarism checker works by taking a piece of text you submit and cross-referencing it against a vast database of written content to find duplicate content.

Using Grammarly Premium’s plagiarism tool is no different. Our online plagiarism checker compares your text to over 16 billion web pages and academic papers stored in ProQuest’s databases. When part of your text matches something written online or in a database, you’ll get a plagiarism alert.

When you use Grammarly’s free online plagiarism check to detect plagiarism, you’ll see an instant report that tells you whether or not plagiarism was found and how many grammar and writing issues are present in your document. Grammarly's plagiarism checker flags specific sentences and provides reference information about the source, calculating an overall originality score for your document. Our plagiarism checker also offers advanced feedback on writing mechanics like grammar and spelling, as well as more complex stylistic issues like word choice, conciseness, tone, and more.

Rest assured, your writing will stay private. Our free plagiarism checker will not make your writing searchable publicly or in any other database. No other plagiarism checkers will see your text.

Plagiarism detection and AI detection are not the same. Plagiarism detection involves comparing a piece of writing to a vast database of previously published works to identify any similarities.

AI detection, as it relates to writing, refers to the ability of artificial intelligence to identify text that was created using AI. However, the increasingly human-like quality of AI writing has made it challenging to detect AI-created content. While AI detection tools may exist, this technology is not reliable.

Grammarly encourages students to honor guidelines from educators and educational institutions and declare their use of AI in their writing if that’s what’s asked of them. To help, Grammarly will show where and how to disclose AI use.