What you can do to a PDF depends on what software you use

A PDF is a file format designed to look the same on any computer or device. That also means PDFs are harder to change than Word documents or spreadsheets. You can edit text, add images, fill forms, delete pages, and rearrange content — but the method depends on whether you use free tools, paid software, or online services.

The most common routes are: using a dedicated PDF editor (paid or free), converting the PDF to another format first, using an online tool, or filling out form fields if the PDF was designed to accept them. Each approach has different limits on what you can change and how much it costs.

Key Takeaways

  • Free PDF editors like PDFtk, LibreOffice Draw, and GIMP let you edit text and images, but have fewer features than paid software like Adobe Acrobat Pro.
  • Online PDF editors work in your web browser and require no download, but upload your file to someone else's server, which matters if the document contains private information.
  • Converting a PDF to Word or another format first makes editing easier but may change the layout, especially if the original PDF has complex formatting or images.
  • If the PDF is a form with fillable boxes, you can often edit just those fields without special software — many PDF readers let you type directly into them.
  • Some PDFs are locked or password-protected to prevent changes; removing that protection requires the password or specialized software.

Using free desktop software to edit PDFs

PDFtk is a command-line tool that works on Windows, Mac, and Linux. It lets you merge, split, rotate, and fill form fields. It does not have a visual editor, so you type commands instead of clicking buttons. This makes it powerful for repetitive tasks but steep for people who prefer a graphical interface.

LibreOffice Draw is free and opens PDFs as editable documents. You can change text, move images, add shapes, and delete content. The trade-off is that complex PDFs sometimes display incorrectly, and saving back to PDF format can shift text or images slightly. LibreOffice works on Windows, Mac, and Linux.

GIMP is a free image editor that opens PDFs as images. This works well if you need to edit the PDF like a picture — drawing, erasing, or adding annotations — but it treats the whole page as one image, so you cannot select and move individual text blocks the way you can in a word processor.

All three are free to download and use. None require a subscription or account. The downside is that they have fewer features than Adobe Acrobat Pro, and customer support is limited to online forums and documentation.

Using paid software: Adobe Acrobat Pro and alternatives

Adobe Acrobat Pro is the standard tool for PDF editing. It lets you edit text and images directly, add or delete pages, rearrange content, and fill forms. It also handles password-protected PDFs if you have the password. Acrobat Pro costs money — typically a monthly subscription through Adobe's website — and requires a download.

Other paid options include Nitro Pro and PDFpenPro (Mac only). Both offer similar features to Acrobat Pro at different price points. Nitro Pro is often cheaper upfront but may have fewer advanced features. PDFpenPro is designed specifically for Mac and integrates with Apple's ecosystem.

Paid software usually includes better customer support, more reliable handling of complex PDFs, and faster performance on large files. The cost is the main barrier — most charge either a one-time purchase fee or a monthly subscription.

Converting a PDF to another format before editing

If you want to edit a PDF as if it were a Word document, you can convert it first. Tools like Smallpdf, ILovePDF, and CloudConvert convert PDFs to Word (.docx), Excel (.xlsx), or other formats. You then edit the converted file in Microsoft Word, Google Docs, or another program, and save it back to PDF if needed.

The advantage is that you get all the editing power of Word or Excel. The disadvantage is that conversion often breaks the layout, especially if the original PDF has multiple columns, images, or unusual fonts. Text may reflow, images may move, and spacing may change. This works best for simple PDFs that are mostly text.

Most conversion tools are free for a limited number of files per month. Unlimited conversion usually requires a paid account. The process is straightforward: upload the PDF, choose the output format, download the converted file.

Using online PDF editors

Online tools like Smallpdf, ILovePDF, PDFcandy, and Sejda let you edit PDFs in your web browser without downloading software. You upload the file, make changes (add text, delete pages, rotate, merge), and download the result. Most offer a free tier with limits on file size or number of edits per month.

The main advantage is convenience — no installation, no learning a new program. The main disadvantage is that you upload your file to someone else's server. If the PDF contains sensitive information (medical records, financial statements, personal data), this may not be safe. Check the tool's privacy policy before uploading.

Most online editors handle basic tasks well but struggle with complex PDFs or large files. They are fastest for simple jobs like adding a signature, filling a form, or deleting a page.

Filling out PDF forms without editing the document

Many PDFs are designed as forms with fillable fields — boxes where you type your name, address, or other information. If the PDF has these fields, you can fill them in using almost any PDF reader, including the free Adobe Reader. You do not need to edit the PDF itself; you just type into the boxes.

To check if a PDF has fillable fields, open it in Adobe Reader or your default PDF viewer and try clicking on a box. If the cursor changes to a text cursor and you can type, the field is fillable. If nothing happens, the form was created as an image or locked text, and you will need to edit the PDF itself using one of the methods above.

Fillable forms are the easiest option because they require no special software and preserve the original layout. The form creator designed the boxes to accept your input, so there is no risk of text shifting or images moving.

Removing password protection from a PDF

Some PDFs are locked with a password to prevent editing or copying. If you have the password, most PDF editors (free or paid) will let you unlock the file by entering it. If you do not have the password, removing the protection is much harder and may not be legal depending on why the PDF was locked and where you live.

Tools like PDFtk and online services claim to remove passwords, but they work only on PDFs with weak encryption or no owner password. Strong encryption cannot be broken without the password. Before using a password-removal tool, make sure you have the right to edit the document — for example, it is your own file or the owner gave you permission.

Frequently Asked Questions

Can I edit a PDF on my phone or tablet?

Yes, but with limits. Apps like Adobe Acrobat Reader (free) and Adobe Acrobat Pro (paid subscription) let you fill forms and add annotations on iOS and Android. Full editing — changing text, deleting pages, rearranging content — is usually only available in the paid version. Online editors also work on phones if you have a web browser.

Will editing a PDF change how it looks when someone else opens it?

Usually not, but it depends on the tool and the PDF. Adobe Acrobat Pro is most reliable at preserving layout. Free tools like LibreOffice Draw sometimes shift text or images slightly. If you convert to Word first, the layout often changes significantly. Test by opening the edited PDF on another computer before sending it to someone else.

What if the PDF is scanned from paper and is just an image?

A scanned PDF is a picture of text, not actual text. Standard text editors cannot change it. You would need to use GIMP or another image editor to draw over it, or use optical character recognition (OCR) software to convert the image to editable text first. Many online PDF tools and Adobe Acrobat Pro include OCR.

Is it safe to upload my PDF to an online editor?

It depends on the tool and the content. Reputable services like Smallpdf and Adobe encrypt files in transit and delete them after a set time. But if the PDF contains medical records, tax returns, or other sensitive data, uploading to any third-party server carries risk. For sensitive documents, use desktop software instead.

Can I undo changes after I save an edited PDF?

Not usually. Most PDF editors do not keep a version history the way Google Docs or Word does. Save a copy of the original PDF before making changes, so you can go back to it if needed. Some tools like Adobe Acrobat Pro let you undo recent changes within the same session, but once you close and reopen the file, undo is no longer available.