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Best PDF Grammar Checker Online Tools and Apps

With the advancement of proofreading and grammar-checking tools, you can enhance your writing skills to new levels. Most word processing tools have some sort of proofreader built into them, but other than that, you cannot easily find a good dedicated PDF grammar checker tool on the market.

In this article, we discuss a few PDF grammar check online or offline tools if you are looking for a good dedicated tool. So, we recommend reading the article in full and learning more about some great PDF spelling and grammar check options, and then we choose the best one.

How to Grammar Check PDF with UPDF

UPDF AI now employs ChatGPT as their go-to feature if you are looking to check your grammar of writing. You can also translate PDF text into any language other than checking grammar. While you are at it, you can also summarize whatever document you are working on in easy-to-understand text all just to remove any mistakes you may have made while writing. Following are simple and easy steps to use the PDF grammar checker.

  1. Open your PDF document in UPDF and click on the UPDF AI button on the bottom side of the ribbon on the left, as you can see in the image.
  1. Click on the Chat tab on the top left, and copy any sentence or paragraph from the text by selecting it.
  2. In the chat box, you need to paste the copied text using the following command line: "Check grammar: [paste the copied content]."
  3. You don't need to add the inverted commas here or in parentheses; these are for representation only. You can observe the correct way, as shown in the image below.
  1. Just press Enter, and the AI will give you recommendations to improve the text grammatically. Using similar prompts, you can also check for spelling mistakes.
  2. With these suggestions from the PDF grammar checker, if you need to make any changes, you can go to the "Edit PDF" mode to write much better.

How to Grammar Check PDF with online-spellcheck.com

Online-spellcheck.com is a PDF grammar check online that can help you to check the grammar and spelling mistakes in your document easily and quickly.

  1. Visit the website and paste the copied text into the text box you see in the image below.
  1. Press the black "CHECK TEXT" on the lower right and let it analyze the text and give suggestions.
  2. You can then copy the corrected text, Download it as text or PDF, or save it into a file format you prefer from the green buttons just below the corrected text.
  3. You can also click on highlighted words and get a description of what and why it was corrected.
  4. Other than copying and pasting text into the text box, you can also "Enter a URL", "Upload a File", or "Upload from Cloud" to check and use the PDF grammar checker feature.

How to Grammar Check PDF with WhiteSmoke

WhiteSmoke is another online grammar check for PDFs that you can use to correct your writing by simply copying and pasting what you want to check. The free tool is very limited and only supports 250 characters at the moment, which isn't a lot.

If you want to use the full functionality of this tool, you need to pay for the Full Version. Here is how you can use it to check grammar in PDFs free of charge.

  1. Open the website and scroll down to the text box.
  2. Copy and paste the text you want to check and click on the "Check Text" button.

How to Choose the Best PDF Grammar Checker

Now that we have shared three different PDF grammar checker tools with you let's compare them to see which is the best tool for your writing.

PDF grammar checker ToolGreat FeaturesCons
UPDF1. UPDF AI grammar checking
2. No limit on the word count
3. Give suggestions for better writing
4. Many other features enhance your writing, such as translating, summarizing, etc.
Online-spellcheck.com1. PDF spelling and grammar check
2. There are many ways to upload and download text and documents
3. Offers reasons and suggestions for better writing or mistakes
1. Grammar, spelling, punctuation, and style correction
WhiteSmoke1. Grammar, spelling, punctuation, and style correction1. Only 250 characters allowed
2. No added features
3. You need to buy the Full version to be useful at all

As you can see from the table and the comparison, as a PDF grammar checker tool, UPDF offers much more in terms of functionality than the others. It is a complete software with a reader, writer, editor, and AI tool combined.


When it comes to making a document with perfect grammar and context, UPDF has come out on top. When you are writing, you don't only need PDF spelling and grammar checks, but you need to add images, edit text, and much more. UPDF does that all within the app, and you don't need to take the help of any PDF grammar check online.

Therefore, we recommend you download the UPDF and learn more about the excellent app and the fantastic discount they are offering right now.

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