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Grammarly Plagiarism Checker Review

Searching for a plagiarism checker? Read our review of the Grammarly Plagiarism Checker and how it compares to the alternatives.

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Introduction

Our text compare tool is a fantastic, lightweight tool that provides plagiarism checks between two documents. Whether you are a student, blogger or publisher, this tool offers a great solution to detect and compare similarities between any two pieces of text. In this article, I will discuss the different ways to use the tool, the primary features of the tool and who this tool is for. There is an FAQ at the bottom if you run into any issues when trying to use the tool.

What makes Originality.ai’s text comparison tool stand out?

Keyword density helper – This tool comes with a built-in keyword density helper in some ways similar to the likes of SurferSEO or MarketMuse the difference being, ours is free! This feature shows the user the frequency of single or two word keywords in a document, meaning you can easily compare an article you have written against a competitor to see the major differences in keyword densities. This is especially useful for SEO’s who are looking to optimize their blog content for search engines and improve the blog’s visibility.

Ways to compare

File compare – Text comparison between files is a breeze with our tool. Simply select the files you would like to compare, hit “Upload” and our tool will automatically insert the content into the text area, then simply hit “Compare” and let our tool show you where the differences in the text are. By uploading a file, you can still check the keyword density in your content.

URL compare

Comparing text between URLs is effortless with our tool. Simply paste the URL you would like to get the content from (in our example we use a fantastic blog post by Sherice Jacob found here) hit “Submit URL” and our tool will automatically retrieve the contents of the page and paste it into the text area, then simply click “Compare” and let our tool highlight the difference between the URLs. This feature is especially useful for checking keyword density between pages!

Simple text compare

You can also easily compare text by copying and pasting it into each field, as demonstrated below.

Features of Originality.ai’s Text Compare Tool

Ease of use

Our text compare tool is created with the user in mind, it is designed to be accessible to everyone. Our tool allows users to upload files or enter a URL to extract text, this along with the lightweight design ensures a seamless experience. The interface is simple and straightforward, making it easy for users to compare text and detect the diff.

Multiple text file format support

Our tool provides support for a variety of different text files and microsoft word formats including pdf file, .docx, .odt, .doc, and .txt, giving users the ability to compare text from different sources with ease. This makes it a great solution for students, bloggers, and publishers who are looking for file comparison in different formats.

Protects intellectual property

Our text comparison tool helps you protect your intellectual property and helps prevent plagiarism. This tool provides an accurate comparison of texts, making it easy to ensure that your work is original and not copied from other sources. Our tool is a valuable resource for anyone looking to maintain the originality of their content.

User Data Privacy

Our text compare tool is secure and protects user data privacy. No data is ever saved to the tool, the users’ text is only scanned and pasted into the tool’s text area. This makes certain that users can use our tool with confidence, knowing their data is safe and secure.

Compatibility

Our text comparison tool is designed to work seamlessly across all size devices, ensuring maximum compatibility no matter your screen size. Whether you are using a large desktop monitor, a small laptop, a tablet or a smartphone, this tool adjusts to your screen size. This means that users can compare texts and detect the diff anywhere without the need for specialized hardware or software. This level of accessibility makes it an ideal solution for students or bloggers who value the originality of their work and need to compare text online anywhere at any time.

If you are an avid follower of this blog, you’ll know we often talk about the importance of transparency in the future of digital content.

With more and more people using AI content creation tools, and an ever-increasing amount of content getting published online, the chances of plagiarism occurring is also on the rise.

Simultaneously, the trust readers have in what they are consuming is also dropping.

The only way to resolve this issue is by providing readers with transparency, which can be done by using an effective and accurate plagiarism checker.

Here, we’ll review one of the most used tools in this space, the Grammarly Plagiarism Checker, to see whether or not it is a checker you can rely on, or one you should avoid.

Key Takeaways (TL;DR)

  • Originality.ai outperforms Grammarly in Global plagiarism detection.
    • At the 15% threshold (Originality.ai 86% vs. Grammarly 80.3%). 
    • However, at the 5% threshold, Grammarly shows strong performance (Originality.ai 88% vs. Grammarly 93%).
  • Originality.ai is significantly better at identifying Paraphrase plagiarism.
    • At the 15% threshold (Originality.ai 27.62% vs. Grammarly 3%).
    • At the 5% threshold (Originality.ai 34.7% vs. Grammarly 14%).
  • Originality.ai has a notable lead in identifying Patchwork plagiarism.
    • At the 15% threshold (Originality.ai 43.5% vs. Grammarly 43%).
    • At the 5% threshold (Originality.ai 65% vs. Grammarly 51%).

Grammarly Plagiarism Checker Quick Review

  • Ease of use - 8/10
  • Features - 6/10
  • Customer Support - 7/10
  • Price - 8/10
  • Speed - 8/10
  • Performance - 6/10
  • Summary - 7/10

In brief, while the Grammarly grammar checker tool is right up there with the very best, their plagiarism checker isn’t quite as good.

While it certainly is a solid option, and better than many tools on offer, it isn’t quite as effective as some of the market-leaders, such as Originality.ai.

What Is The Grammarly Plagiarism Checker?

Since its inception, Grammarly has rapidly grown in popularity, quickly becoming one of the most popular tools for checking and improving grammar. 

The results are quick, the built-in Chrome Extension is easy to manage, and the results have allowed many users to ensure their work is grammar-free and of the highest quality.

Since then, Grammarly has opted to explore other elements of online content creation, most recently publishing the Grammarly AI detector.

Among their ventures is a plagiarism checker, which is designed to help users identify any potential forms of plagiarism, whether intentional or not.

Why are people interested in Grammarly’s Plagiarism Checker?

Having the ability to check for plagiarism has become absolutely essential in our digitally-focused everyday life.

With more and more concerns over the credibility of what people read online and general trust online at an all-time low, it is absolutely crucial that what you post on your website or submit as your own work, is 100% legitimate.

Plagiarism detectors can help achieve this, either allowing you to check the work of others or check your own before submission.

Given the fact that Grammarly has become a household (and reliable) name for grammar checking, it’s no surprise that they have also garnered significant interest in their plagiarism tool.

Who Is the Grammarly Plagiarism Checker Best for?

Grammarly’s plagiarism checker is a great solution for both writers and reviewers of all formats of content, allowing people to gain more transparency in what is getting submitted or published.

Content marketers

Content marketers can greatly benefit from using a tool like Grammarly’s Plagiarism Checker. Whether it’s work they’ve created themselves or work that has come in from a freelance writer, using a plagiarism checker is a great way to maintain the authenticity and quality of the content on your website.

Freelancers

Equally, freelancers can also benefit from using a plagiarism checker like Grammarly’s offering, as this allows them to prove that the content they have produced is legitimate and their own.

Not only does it provide their clients with peace of mind, but it is also a professional and proactive approach to plagiarism detection, which can only improve client relations.

Academics

Last but not least, students and academics can also benefit from using a plagiarism tool like this. Students can use it to give them confidence that they aren’t going to run into any issues with the work they have submitted, and academics can use it to ensure that students aren’t attempting to pass off other people's work as their own, either accidentally or intentionally.

How to Use the Grammarly Plagiarism Checker Effectively

To get the most out of the Grammarly Plagiarism Checker, you can either paste your text into the tool, or upload your chosen file if it is a Word doc or PDF.

Once done, you can press the “Scan for Plagiarism” button to start the process. The platform will then take you to a standard Grammarly page, and you’ll need to click the “Check for Plagiarism and AI” button in the bottom right-hand corner.

The tool will then highlight any potential matches with other documents and flag them as plagiarism. However, unlike Copyscape, the tool shows you all matches, regardless of how minimal they are.

Copyscape will only show results that are more than a certain percentage match, but that isn’t the case with Grammarly.

For example, we pasted this article into the platform, and immediately this was flagged: 

How Much Does It Cost?

While the basic version of the Grammarly tool is free, the plagiarism scanner is not included in this subscription type. Instead, you will need to purchase a Premium, Business, or Enterprise plan.

The Pro Plan - $12 per month (yearly plan)

  • Everything included in the Free Plan
  • Catch accidental plagiarism
  • Rewrite full sentences
  • Adjust your writing tone
  • Write fluently in English

The Business Plan - $15 per month (yearly plan)

  • Everything included in the Pro Plan
  • Catch accidental plagiarism
  • Stay on-brand
  • Analytics dashboard
  • Generate text with 2,000 AI prompts

The Enterprise Plan - Contact sales for pricing

  • Everything included in Pro
  • Dedicated support
  • Enhanced security, privacy, and governance
  • Unlimited generative AI prompts

Alternatives to the Grammarly Plagiarism Checker 

While the Grammarly Plagiarism Checker is a popular choice, it is not the only option available to you.

Infact, there are several other plagiarism tools you could consider, such as the Originality.ai plagiarism checker or Copyscape.

The Originality.ai plagiarism checker is also an industry-leader and a necessity for anyone who is publishing content online, submitting, or reviewing academic content.

Read more about Originality.ai for educators.

Our Plagiarism Tool Test

With all that in mind, we decided to put the Grammarly Plagiarism Checker to the test as part of a wider research piece, comparing it to various other popular plagiarism detection solutions.

As with any research we undertake, the information below is from detailed and unbiased testing, running the same content through each tool to get the fairest possible results.

Our recent study evaluated the effectiveness of popular plagiarism detection tools — Copyscape and Grammarly — with Originality.ai, our unique offering. 

We explored their key features, results, user experience, pricing, and performance in plagiarism detection.

To ensure a fair comparison, we selected a standardized set of texts with varying degrees of originality, paraphrasing, and plagiarism. 

Dataset

  • Total 600 Text Samples:
    • Each sample of under 2500 words
    • 200 samples from each type of plagiarism mentioned below.
  • 3 Types of plagiarism in the selected dataset and its source:
    • Global Plagiarism: 

         PAN Plagiarism Corpus 2011 (PAN-PC-11) 

          Source: https://zenodo.org/records/3250095

  • Paraphrase Plagiarism:

         Identifying Machine-Paraphrased Plagiarism

          Source: https://zenodo.org/records/3608000

  • Patchwork Plagiarism:

          PAN14 Originality - Text Alignment

          Source: https://zenodo.org/records/3716022

The evaluation criteria

We tested each tool using the same evaluation criteria stated below:

  • Sensitivity (True Positive Rate): The percentage of the time the detector identifies plagiarism correctly.
  • Accuracy: The percentage of the detector’s predictions that were correct
  • F1 Score: The harmonic mean of Specificity and Precision, often used as an agglomerating metric when ranking the performance of multiple detectors.

The threshold

We compared these tools at the threshold of 3%, 5%, and 15%.

Threshold: The predetermined percentage of content similarity at which a text will be flagged as plagiarised.

For example, a 15% threshold indicates that if a document has more than 15% matching content from other sources, it will be considered as potentially plagiarised.

Originality.ai vs. Grammarly

Review a comparison of the Originality.ai Plagiarism Checker specifically to Grammarly. The review includes an analysis of plagiarism detection performance in types of plagiarism that include: global, paraphrase, and patchwork plagiarism.

The results clearly show that while Grammarly’s Plagiarism Checker is reliable on a global scale, it struggles to match the Originality.ai Plagiarism Checker in other areas, most notably in paraphrase plagiarism.

Results overview

  • Global plagiarism: At the 15% threshold, Originality.ai (86%) outperforms Grammarly (80.3%). At the 5% threshold, Grammarly (93%) surpasses Originality.ai (88%).
  • Paraphrase plagiarism: Originality.ai is significantly better at both thresholds — 27.62% (15% threshold) and 34.7% (5% threshold) compared to Grammarly’s 3% and 14%.
  • Patchwork plagiarism: Originality.ai has a slight edge at 15% (43.5% vs 43%) and a notable lead at 5% (65% vs 51%).

User experience

Comparison Table
Originality.ai Grammarly
  • User-friendly interface, real-time feedback
  • Easy upload of content via multiple methods (URL, document upload, copy-paste)
  • Detailed plagiarism reports with shareable links
  • Paraphrasing detection for more nuanced forms of plagiarism
  • Provides AI-generated content detection with high accuracy
  • Seamless integration with writing tools (e.g., Word, Google Docs)
  • Real-time plagiarism checks along with editing and grammar-checks

Pricing

Pricing Table
Originality.ai Grammarly
  • Pay As You Go: $60 one-time payment for 6,000 credits (2-year expiry)
  • Pro Plan: $14.95/month for 1,000 credits (monthly renewals)
  • Enterprise Plan: $136.58/month for 15,000 credits with API access
  • Free version limited to 10 scans and 500 words
  • $12/month (billed annually) for Premium subscription
  • $15/month (billed annually) for Business subscription
  • No pay-per-use option
  • No plagiarism detection in free plan

Key features

Key Features Table
Originality.ai Grammarly
  • Detects complex plagiarism forms like patchwork and mosaic plagiarism
  • Very intuitive similarity score for user content compared to plagiarized sources
  • Identifies AI-generated content from various sources
  • Multilingual plagiarism detection
  • Detailed Scan History and Shareable Reports
  • Readability Checker & Fact Checker
  • Plagiarism detection with ProQuest integration
  • Grammar and writing improvement tools
  • Real-time results

Analysis

Scan Time

For scanning 1000-1500 words using API Endpoints:

  • Originality.ai: 20-30 seconds
  • Grammarly: 15-30 seconds (API not available)

Grammarly is useful for writers needing an all-in-one tool, but Originality.ai is more specialized, providing a more comprehensive plagiarism detection experience.

Originality.ai Grammarly
  • Strong for global plagiarism (86%) and patchwork detection (43.5%), with decent paraphrase detection (27.62%)
  • Ideal for content creators, educators, and publishers who need both plagiarism detection and AI content analysis
  • Strong capabilities in detecting both traditional and subtle plagiarism, making it ideal for academic and journalistic use
  • Provides real-time content quality assessment with readability and fact-checking tools
  • Its AI detector that has the ability to detect AI-generated content with 98% accuracy makes it stand out among competitors, especially for professional publishers concerned with content fraud
  • Good for global plagiarism detection (80.3%) and effective for patchwork plagiarism (43%), but very weak at detecting paraphrased content (3%)
  • Best for writers needing both grammar improvement and basic plagiarism checks
  • Not as detailed for academic checks where paraphrasing is done

Pros

Originality.ai Grammarly
  • High accuracy in detecting both AI-generated content and plagiarism
  • User-friendly interface
  • Offers multiple features like readability check, fact check, and paraphrasing detection
  • Shareable and detailed plagiarism reports
  • Pay-as-you-go pricing option for flexibility
  • Flexible pricing – buy a subscription or credits
  • Budget-friendly prices
  • A great number of basic features
  • Accessible website
  • Offers a language and citation assistant
  • Offers rewriting suggestions to decrease plagiarism
  • Catches even common phrases

Cons

Comparison Table
Originality.ai Grammarly
  • API access is only available in the enterprise plan
  • The Pay-as-You-Go plan lacks features like team management, full site scans, and scan from URL
  • Can be inaccurate when checking human content (learn more about false positives)
  • Doesn’t offer a full free version to test all its capabilities
  • No free plans for plagiarism detection
  • Not reliable for edited or paraphrased texts
  • No API for Plagiarism Checker

Thanks to the advanced AI-driven algorithms it uses, the Originality.ai tool is fantastic at detecting all forms of plagiarism in content, including even the most subtle iterations.

Check out the Originality.ai Plagiarism Checker here!

Further Reading on Grammarly

Frequently Asked Questions About The Grammarly Plagiarism Checker

Is Grammarly’s Plagiarism Checker accurate?

The Grammarly Plagiarism Checker is relatively accurate compared to alternative options but not as accurate as some industry-leaders, such as the Originality.ai Plagiarism Checker.

Is Grammarly’s Plagiarism Checker free?

Unfortunately, you can’t use the Grammarly Plagiarism Checker without a Pro, Business, or Enterprise Account.

What sources does Grammarly’s Plagiarism Checker check?

Grammarly’s plagiarism checker scours billions of online sources to identify any potential matches. These sources include academic studies, books, and web pages.

Graeme Whiles

My name is Graeme, a passionate writer with a strong Content Marketing background. Over the last seven years, I have developed an extensive portfolio of SEO Content writing, helping various brands improve their organic traffic, customer experience, and, ultimately, profits!

Frequently Asked Questions

Do I have to fill out the entire form?

No, that’s one of the benefits, only fill out the areas which you think will be relevant to the prompts you require.

Why is the English so poor for some prompts?

When making the tool we had to make each prompt as general as possible to be able to include every kind of input. Not to worry though ChatGPT is smart and will still understand the prompt.

In The Press

Originality.ai has been featured for its accurate ability to detect GPT-3, Chat GPT and GPT-4 generated content. See some of the coverage below…

View All Press
Featured by Leading Publications

Originality.ai did a fantastic job on all three prompts, precisely detecting them as AI-written. Additionally, after I checked with actual human-written textual content, it did determine it as 100% human-generated, which is important.

Vahan Petrosyan

searchenginejournal.com

I use this tool most frequently to check for AI content personally. My most frequent use-case is checking content submitted by freelance writers we work with for AI and plagiarism.

Tom Demers

searchengineland.com

After extensive research and testing, we determined Originality.ai to be the most accurate technology.

Rock Content Team

rockcontent.com

Jon Gillham, Founder of Originality.ai came up with a tool to detect whether the content is written by humans or AI tools. It’s built on such technology that can specifically detect content by ChatGPT-3 — by giving you a spam score of 0-100, with an accuracy of 94%.

Felix Rose-Collins

ranktracker.com

ChatGPT lacks empathy and originality. It’s also recognized as AI-generated content most of the time by plagiarism and AI detectors like Originality.ai

Ashley Stahl

forbes.com

Originality.ai Do give them a shot! 

Sri Krishna

venturebeat.com

For web publishers, Originality.ai will enable you to scan your content seamlessly, see who has checked it previously, and detect if an AI-powered tool was implored.

Industry Trends

analyticsinsight.net

Frequently Asked Questions

Why is it important to check for plagiarism?

Tools for conducting a plagiarism check between two documents online are important as it helps to ensure the originality and authenticity of written work. Plagiarism undermines the value of professional and educational institutions, as well as the integrity of the authors who write articles. By checking for plagiarism, you can ensure the work that you produce is original or properly attributed to the original author. This helps prevent the distribution of copied and misrepresented information.

What is Text Comparison?

Text comparison is the process of taking two or more pieces of text and comparing them to see if there are any similarities, differences and/or plagiarism. The objective of a text comparison is to see if one of the texts has been copied or paraphrased from another text. This text compare tool for plagiarism check between two documents has been built to help you streamline that process by finding the discrepancies with ease.

How do Text Comparison Tools Work?

Text comparison tools work by analyzing and comparing the contents of two or more text documents to find similarities and differences between them. This is typically done by breaking the texts down into smaller units such as sentences or phrases, and then calculating a similarity score based on the number of identical or nearly identical units. The comparison may be based on the exact wording of the text, or it may take into account synonyms and other variations in language. The results of the comparison are usually presented in the form of a report or visual representation, highlighting the similarities and differences between the texts.

String comparison is a fundamental operation in text comparison tools that involves comparing two sequences of characters to determine if they are identical or not. This comparison can be done at the character level or at a higher level, such as the word or sentence level.

The most basic form of string comparison is the equality test, where the two strings are compared character by character and a Boolean result indicating whether they are equal or not is returned. More sophisticated string comparison algorithms use heuristics and statistical models to determine the similarity between two strings, even if they are not exactly the same. These algorithms often use techniques such as edit distance, which measures the minimum number of operations (such as insertions, deletions, and substitutions) required to transform one string into another.

Another common technique for string comparison is n-gram analysis, where the strings are divided into overlapping sequences of characters (n-grams) and the frequency of each n-gram is compared between the two strings. This allows for a more nuanced comparison that takes into account partial similarities, rather than just exact matches.

String comparison is a crucial component of text comparison tools, as it forms the basis for determining the similarities and differences between texts. The results of the string comparison can then be used to generate a report or visual representation of the similarities and differences between the texts.

What is Syntax Highlighting?

Syntax highlighting is a feature of text editors and integrated development environments (IDEs) that helps to visually distinguish different elements of a code or markup language. It does this by coloring different elements of the code, such as keywords, variables, functions, and operators, based on a predefined set of rules.

The purpose of syntax highlighting is to make the code easier to read and understand, by drawing attention to the different elements and their structure. For example, keywords may be colored in a different hue to emphasize their importance, while comments or strings may be colored differently to distinguish them from the code itself. This helps to make the code more readable, reducing the cognitive load of the reader and making it easier to identify potential syntax errors.

How Can I Conduct a Plagiarism Check between Two Documents Online?

With our tool it’s easy, just enter or upload some text, click on the button “Compare text” and the tool will automatically display the diff between the two texts.

What Are the Benefits of Using a Text Compare Tool?

Using text comparison tools is much easier, more efficient, and more reliable than proofreading a piece of text by hand. Eliminate the risk of human error by using a tool to detect and display the text difference within seconds.

What Files Can You Inspect with This Text Compare Tool?

We have support for the file extensions .pdf, .docx, .odt, .doc and .txt. You can also enter your text or copy and paste text to compare.

Will My Data Be Shared?

There is never any data saved by the tool, when you hit “Upload” we are just scanning the text and pasting it into our text area so with our text compare tool, no data ever enters our servers.

Software License Agreement

Copyright © 2023, Originality.ai

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

  1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

  1. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Will My Data Be Shared?

This table below shows a heat map of features on other sites compared to ours as you can see we almost have greens across the board!

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