I tried using Quillbot and Grammarly, but they sometimes give inappropriate edits, or not enough information to justify edits so I am often left confused. Any suggestion would be helpful.

P.S: If such a question already exists on this forum, please guide me towards it.

5 Answers 5


To the best of my knowledge, no grammar checker yet developed is "reliable" enough to never or rarely give incorrect suggestions. This includes commercial as well as free ones. The best that such software can do at present is make suggestions that a human must evaluate.

This is, at least in significant part, because the "rules" of English grammar do not form a logical algorithmic system. There are many exceptions and special cases that must be learned individually, and things that are "correct" in one context are not in another. And "incorrect" grammar is perfectly proper is some cases, such as when writing dialog.

  • 10
    This. As you say, even if "free to use" was removed from the question, the answer would be the same. Sep 12, 2021 at 7:39
  • 3
    partly because there's quite a difference between "correct" and "unambiguous"/"easy to understand"
    – somebody
    Sep 12, 2021 at 16:25
  • 5
    @somebody Quite true, but also because the "rules" of English grammar do not form a logical algorithmic system. There are many exceptions and special cases that must be learned individually, and things that are "correct" in one context are not in another. And "incorrect" grammar is perfectly proper is some cases, such as when writing dialog. Sep 12, 2021 at 16:38
  • 9
    @somebody The complexity of grammar is not something unique to English, but extremely prevalent in all natural languages. The languages with the most simple and regular grammars tend to actually be pidgins, of which English is not one by any stretch. Sep 13, 2021 at 9:06
  • 6
    @somebody What makes you think that a grammar checker couldn't produce a suggestion which was completely wrong? They are programmed by humans, who are fallible; and by necessity they make generalisations, which are not always applicable. See for instance this question, where Grammarly incorrectly suggested an article before "thou", presumably because it analysed it as a noun.
    – IMSoP
    Sep 13, 2021 at 14:24

English grammar is a bit of a mess. Even smart humans can disagree about the correctness of a particular grammatical construction. You ask a great deal of an application, free or otherwise, to be "reliable."

I use several of these programs. I even pay for a few. Their value to me is in focusing my attention on particular passages that may or may not need correction. Almost all of these programs have a "ignore" function, either for a particular instance or for a whole class of grammatical tests. I use these functions and so should you.

Even if they worked perfectly (whatever that means), fictional works may have, for good and proper reasons, material that is decidedly non-grammatical. "And that ain't none of their business, buster!"

In the end, the author owns the writing. Spelling, grammar, and even style checks are only tools in the employ of the author.

  • 2
    "English grammar is a bit of a mess." -- what an understatement...
    – boatcoder
    Sep 15, 2021 at 0:30

Checking grammar using a computer program has indeed turned out to be much harder than computer scientists thought when the computer was a new concept. Some even thought natural language, logic, and all the rest would be something the computer would be able to deal with in a jiffy.

I think computer science has contributed to language studies the fact that language is way more complex than a simple algorithm.

That being said, Grammarly is a tool that will grammar check English and it has a free edition. (ProWritingAid is another tool, but I haven't looked into it much—it does seem to have a free edition though).

Is Grammarly any good? It does help me find small problems when I write, however, more importantly, it will do this by forcing my text into their cookie-cutter idea of a grammatically correct text.

And yes, Grammarly does sometimes get the grammar wrong and suggests things that don't seem right...

I would never, ever, use Grammarly (or any other tool) for anything but blog posts, texts on places like Writing.SE, and work-related texts in English.

For fiction (even if I wrote in English) I'd rely on beta readers, editors, and so on... Never a program... mainly because, as I mentioned, you might lose your style and voice if your English will be forced into their idea of good language.

  • 2
    The free edition of ProWritingAid is limited to 500 words at a time.
    – GammaGames
    Sep 13, 2021 at 14:10
  • 8
    I'd go further with your first sentence, and say that analysing grammar at all has turned out to be much harder than linguists thought. Some of the more dubious grammar "rules" come from misguided attempts to squeeze English into unnatural shapes for the convenience of scholars, rather than reflecting how it has been naturally and successfully used for centuries.
    – IMSoP
    Sep 13, 2021 at 14:21

I know this might not the answer that you expected, but it is better to master English grammar and syntax with your own brain, something that no computer can do, and to use that skill to write and revise. Then you will not need to depend on any algorithm, and your own skills will be superior to them. Knowing grammar and syntax will not only enable you to write correctly, but with variety and rhythm as well. By depending on an algorithm, you are limiting yourself to the same syntactic choices, because the algorithm cannot recommend ones which are better in every circumstance.

But I'm not a professional writer. I just know that it is better to have your own language skills than to depend on a computer, and I know this for many reasons.

As for myself, I'm still not fully skilled at English syntax.



Open a new email on Gmail, don't fill the To: field, paste the text you want to check on body and wait for the online grammar (and idiomatic!) checker points out any mistakes or suggestions.

Actual use: English is not my first language and I checked this text as above. Gmail suggested: "point" to "points out".

  • This is a great idea, I can't imagine why it never occurred to me.
    – uhoh
    Sep 15, 2021 at 4:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.