How to Edit a PDF for Free: Add Text, Sign, and Fill Forms

What Editing a PDF Can Mean

"Edit a PDF" covers three different jobs. Knowing which one you need tells you which tool to reach for.

Adding something on top of a page

Typing on a form, adding a signature, highlighting a sentence, stamping an image. The original page stays as it is, and your additions are drawn over it. This is the most common kind of edit, and the easiest.

Changing what's already on a page

Rewording a sentence, fixing a typo, or replacing a number in the existing text. This is the hard one, for reasons explained in the next section.

Changing the pages themselves

Putting pages in a new order, removing a page, turning a sideways scan, or joining several files into one. Each of these is a separate, simple job with its own tool.

Why You Can't Just Retype Text in a PDF

A Word document stores paragraphs. When you change a word, the program reflows the rest of the line and the page. A PDF stores finished pages instead. Each piece of text is placed at a fixed position, often a word or a few letters at a time, and the file may only include the characters of the font it actually used.

That's what makes a PDF look identical everywhere, and it's also why changing a word is awkward. There are no paragraphs to reflow. A longer word overlaps the next one, and a letter that wasn't in the embedded font may not exist at all. Desktop editors work around this, with mixed results.

If you have the original document, editing it and exporting a new PDF is almost always cleaner. If you don't, the practical fix is to cover the old text with a white box and type the new text on top.

How to Edit a PDF Online for Free

For additions, a browser editor is the quickest route. You can edit a PDF online with our free editor, which works on your own device. Here's the process:

1. Open the PDF. Every page appears in the editor.
2. Pick a tool: Text to type, Highlight or Whiteout to drag a box, Draw for freehand, or Image to place a picture.
3. Click or drag on the page. Use Select to move or resize what you added, and Undo if you slip.
4. Save the PDF and download it.

The text you add uses a standard font that covers English and most Western European languages. Characters outside that set, such as emoji or Chinese, can't be saved with it.

How to Fill In a PDF Form

Forms with fillable fields

Some PDFs have real form fields, the boxes you can click into in a PDF viewer. Most browsers and PDF readers let you type into these directly and save the result, so try that first.

Scanned forms and forms without fields

Many forms are just a picture of a printed page, or a PDF made without fields. Here you type on top of the page instead. Click at the start of each blank line, type, and nudge the text into place so it sits on the line. Using a size close to the form's own print, often 10 to 12 points, keeps it looking natural.

How to Sign a PDF

A drawn or pasted signature

The everyday way to sign a PDF is to draw your signature with a mouse, trackpad, or finger, or to add a photo of your signature as an image. For the photo, sign on plain white paper, shoot it in good light, and crop it close. A thin pen setting, around 2 points, looks most like ink.

Electronic signature vs digital signature

These two terms sound alike but mean different things. A drawn or pasted signature is an electronic signature. US law under the ESIGN Act of 2000 defines one broadly, as a sound, symbol, or process attached to a record with the intent to sign it, and in the European Union the eIDAS regulation sets the rules.

A digital signature is a cryptographic seal tied to a certificate. It proves who signed and shows whether the file changed afterward. Some contracts, government forms, and businesses ask for this kind specifically. Rules differ by country and by document, so if you're unsure, ask the person you're sending it to what they accept.

Covering Information: Whiteout vs Redaction

Drawing a white or black box over text hides it on screen and on paper. It doesn't remove it from the file. The words are still there underneath, and anyone can select, copy, or search for them.

This has caught out professionals. In 2005, a US military report released as a PDF had sensitive passages covered with opaque boxes, and readers recovered the hidden text simply by copying and pasting it. A legal brief filed by AT&T in 2006 leaked the same way.

To hide private details before sharing a file, you have two safe options:

• Use a real redaction tool, which deletes the content under the box rather than covering it.
• Cover the details, then save each page as an image with PDF to JPG. An image keeps only what's visible, so nothing is left underneath.

Whiteout is still the right tool for fixing a typo or an old date, where nothing secret is involved.

Rearranging, Removing, and Combining Pages

Page-level edits don't touch the content of a page, so each has a simple, dedicated tool:

• Put pages in a new order with Reorder PDF Pages.
• Take out a blank or duplicate page with Delete PDF Pages.
• Fix a sideways scan with Rotate PDF.
• Join a signed page back into the full document with Merge PDF.

Which Tool for Which Edit

When You Need Desktop Software

A free browser editor covers everyday jobs. Paid desktop software earns its place when you need to:

• Rewrite existing text and have the page reflow around it.
• Build a form with real fillable fields.
• Apply a certificate-based digital signature.
• Redact content so it's permanently removed, across many pages at once.
• Turn a scan into searchable, editable text with OCR.

Is It Safe to Edit a PDF Online?

Forms and contracts often carry an address, an ID number, or a signature, so it's worth knowing where the file goes. Many online editors upload it to a server to do the work. A browser-based editor reads and saves the file on your own device instead. Our guide on whether online PDF tools are safe shows how to check any tool yourself in about a minute.

Frequently Asked Questions