Spell- and grammar-checker for PDF documents

Question

I am looking for a program that can spell-check a PDF document (without having to convert the PDF into another format like .docx, which I can do using Adobe Acrobate Pro). If possible, free, compatible with Windows 7 (otherwise Linux) and also checks for the grammar.

Answer 1

For a free, cross platform, application you can use LibreOffice Writer - it will open pdf documents read and write them, (other than password protected documents that you don't have the password and documents from some scanners which are actually image collections), you can spell & grammar check in a wide range of languages.

• Free
• Read & Write pdf files
• Spell Check - 70 or 80 languages supported
• Grammar Check
• Language Tool Extension - can check for mixing up there/their, no/now, etc.
• Windows/Linux/Mac OSX
• Part of a full free, cross platform, office suite.

Screenshot of checking a pdf a fiend was sent:

Answer 2

For a paid option, you can try an Adobe Acrobat script called Spell Check Suite for $85. They do have a free demo here which allows you to check the first page of a document.

This suite of tools adds full spell-checking capabilities to Acrobat. You can now check and mark up regular text and bookmarks in addition to the standard check for form fields and comments which already exists in Acrobat.

Features:

• Compatible with Adobe Acrobat (free or paid) on any platform
• Spell check 33 languages
  • You can select which language you wish to spell check prior to checking the document
• Spell check either the whole document or just a selection
• I am unsure if it changes the incorrect words as I have not used this software myself, but it does notify you of the misspelled words and suggestions for the correct spelling. Much like spell checker on word.
• Add/remove words from dictionaries (different dictionaries for each language)
• Unfortunately, no grammar checking

Screenshots:

Spell check menu

Language select

Highlighted words that are misspelled

Spell check zones

Answer 3

A large number of grammar check softwares out there allow documents with extensions docx and rtf. Therefore, the following is a flexible approach in my opinion.

Step 1. Upload the pdf file in google drive.
Step 2. Open the file with google doc.
Step 3. Grammar check in google doc,
or download in a suitable format and grammar check using another grammar-check software.

By the way, google doc performs good in terms of grammar correction (reported to be better than MS Word; see the link at the end of the answer). Besides, you can download the file as docx file, rtf file, html file, or txt file, and then grammar check using a grammar check software of your choice.

Pros

• No need to worry about mathematical equations messing up your document to be grammar checked (happens when you copy-and-paste or export to another format such as html).
• A portable solution independent of O/S.

Cons

• Rendering equations is still not perfect and you may get lack of white-space errors around math equations (this happens for most alternate solutions too).
• (Potential con) Images are not rendered well, which means text inside images may not be output correctly, though there is no problem with image captions.

Bonus: Here is a comparison of various grammar check tools along the lines of test run- https://medium.com/writers-blokke/can-ai-really-improve-your-writing-9bc3e6440973 (caution: many popular grammar-check softwares use machine learning, and hence their performance is likely to improve with time; the above comparison cannot be relied after a long time).

PS: The above pros-and-cons list is not meant to be exhaustive. Feel free to comment more pros/cons you know.