The Best Plagiarism and Grammar Checkers 

Checking for possibly plagiarized or duplicate content and checking for grammatical errors are two final steps of the writing process that you never want to miss. Below is a comprehensive guide to the software and online tools that provide screening for just plagiarism, just grammar, or both plagiarism and grammar. 

We know that each business is going to have different needs, so we’ve included a wide variety to ensure that you get everything you’re looking for in an editing tool, but also that you don’t overpay for unnecessary extra features. 

Both Plagiarism and Grammar Checking

Grammarly (free version)

The free tier of Grammarly isn’t only online—you’ll never have to enter a credit card to get access to the web app, browser plugin, the desktop app, and the MS Word plugin. The feedback you get with the free version isn’t as robust as the premium version, but it’ll help you avoid the most basic mistakes. 


Grammarly has really done the most for their marketing campaigns—of any of the tools on this list, Grammarly is most likely the one you’ve heard of before. You might even already have a Grammarly browser extension—signified by the little green circle in the bottom-right-hand corner of online text boxes—but many people don’t realize that the paid version of Grammarly offers a ton of useful features, with the kind of writing feedback it provides constantly expanding. Grammarly checks for grammatical correctness, but also for stylistic elements like conciseness, readability, vocabulary, and desired tone. When it comes to plagiarism checking, Grammarly’s advanced duplicate content-checking capabilities are included in the price of a premium subscription, which is usually $29.95 a month or $139.95 a year. 


Although fewer people know about ProWritingAid compared to Grammarly, it’s a very similar—and actually cheaper—program. Grammarly is perhaps a bit more user-friendly than ProWritingAid, but ProWritingAid has basically all the same features and even integrates with more desktop apps than Grammarly, most notably with Scrivener, the writing software favored by book authors and screenwriters. There’s a rudimentary free version of ProWritingAid, but ProWritingAid Premium is $79 a year. If you want plagiarism checking, however, you have to pay a little extra ($89 a year) for Premium+. 


WhiteSmoke is another all-in-one text proofreading contender, as it also checks for grammar, punctuation, spelling and style. Unlike Grammarly and ProWritingAid, however, WhiteSmoke offers the unique benefit of supporting 55 languages (Grammarly and ProWritingAid only support English). WhiteSmoke also offers Statistical Machine Translation services, which they say are aided by the analysis of “leading linguistic experts.” WhiteSmoke’s pricing tiers are little different than Grammarly or ProWritingAid—you can currently pay only $59.95 for a full year of exclusively online service (it’s $79.95 for the addition of desktop compatibility), but both versions include 500 plagiarism checks (with more available for purchase).

Just Plagiarism Screening

All of the above tools are marketed towards writers of all kinds, but since they all require a bit of an investment, they’re especially geared towards students or new writers—people who do a lot of writing and need a lot of help. If you’re a writer who already works with a professional editor and/or proofreader, you’ll likely just want technology that can make sure you haven’t accidentally plagiarized, or that other people aren’t plagiarizing your own writing. There are also some free options included here, which you could use in conjunction with a free grammar checker and not have to pay a cent for the entire proofreading process.  


Quetext is marketed towards all kinds of writers—it checks for plagiarism and doesn’t do much else (but that could very well be all you need). Without paying, you can check 5 pieces a month for free. It has a beautiful interface that’s easy to navigate, and for $9.99 a month (there is no annual payment option) you can get unlimited plagiarism checks, more accurate screenings (with a feature they call DeepSearch), and a citation assistant that turns smaller sections of plagiarized material into appropriately cited references in the style of your choice. 


Duplichecker and SmallSEOTools are two very similar sites. All of their services are free (though you will have to deal with ads), and in addition to offering plagiarism checkers, they both have additional SEO-related tools that are useful for website owners and other people who write for websites. 


Copyscape works a little differently than the above plagiarism checkers—its features are geared more towards website owners and bloggers. Its only free functionality is a reverse plagiarism checker—i.e. you put in a link and Copyscape checks to see if there are websites containing copied content from the linked site. Copyscape Premium is more similar to your standard plagiarism checker, but instead of paying for a subscription you purchase credits depending on how many total words you need to have screened (it’s 3 cents for the first 200 words and then 1 cent for each additional 100 words). Their services are well-known and trusted—if you’re a freelance writer, telling clients that you’ve run your piece for them through Copyscape is a great way to guarantee that your copy is 100% original. 

Just Grammar Checking

If you’re a writer who’s just writing for yourself, you don’t often paraphrase or refer to other published content while you write, or if you mostly just write emails, you might only need something that’s a few steps above your standard spell check feature. 

Hemingway Editor

Author Ernest Hemingway was famous for being an incredibly concise, impactful writer. The Hemingway app—both the free online version and the $19.99 desktop app—strive to make your writing a little bit more like Hemingway’s. It doesn’t actually check for grammar in any significant way, but it’s a great tool to run your writing through after using the free version of Grammarly. Hemingway highlights convoluted sentences, unnecessary modifiers, passive voice, and other style-weakening elements of your writing—basically, it does a lot of what the paid version of other grammar checkers do. It’s good to take each of its recommendations with a grain of salt, but it can help you become aware of less-than-ideal writing tendencies and to become a better writer in the long run. 

Enlist in the Help of a Professional Copywriting Agency

Althought the available editing technology today can do a lot, the abilities of a human proofreader will never be fully replaceable. Online checkers don’t take into account voice, tone, style, and nuance quite like a copywriting agency. Our professional writers and copyeditors are ready to write and edit your copy to perfection. Contact a member of our team today to get started!