How to Edit and Sign a PDF for Free (What Really Changes)

You can edit a PDF for free by adding text, images, drawings and a signature on top of the page, by covering old text and typing over it, by filling its form fields, or by converting it to Word and back. What you usually cannot do is rewrite existing paragraphs as if it were a Word document, because a PDF stores positioned characters, not flowing text. If you still have the original Word or Google Docs file, editing that and exporting a new PDF is the cleanest option.

Why PDFs are hard to edit

PDF was designed to make a document look identical on every screen and printer, not to be edited. A Word file stores paragraphs and rules for wrapping text. A PDF stores the result: instructions such as "draw these characters, in this font and size, at this point on the page". A line may be one instruction or many separate pieces, and nothing in the file says which lines form a paragraph.

• No reflow. If you lengthen a sentence, the following lines do not move down. Editors that try to reflow text have to guess where paragraphs are, which often goes wrong in columns and tables.
• Subset fonts. To keep files small, most PDFs embed only the characters the document uses. If no word contains a "q", the embedded font may have no "q", so the editor substitutes a similar font that may not match.
• Scanned pages are pictures. A scan has no text to edit unless OCR (optical character recognition) has been run on it.
• Restrictions. Some PDFs carry permissions that ask software to block editing or copying. If the document is yours, Unlock PDF can remove a password and those restrictions; only do this for files you are entitled to change.

The realistic ways to edit a PDF

Add text, images and drawings on top

This is the safest edit, because it never damages what is already there. You place a text box, a picture such as a logo, a shape, a highlight or a freehand drawing, and the editor writes it into the PDF as an extra layer. It suits forms without fillable fields or a date next to a signature line.

Edit the existing text line by line

Some editors, including our Edit PDF tool, let you click a line of the PDF's own text and change it in place. Behind the scenes the editor finds the characters of that line, removes them from the page and types your new version in their place, in the closest standard font (Helvetica, Times or Courier, with bold and italic matched) and in the original size and colour. Because the embedded font is usually a subset, the exact original typeface cannot be reused for new letters, so a sharp eye may notice a slightly different font. Each line is edited on its own: a longer sentence does not flow onto the next line. This works for fixing names, dates, amounts and typos; for rewriting paragraphs, convert to Word instead.

When the old characters cannot be removed safely, for example when the text sits inside an embedded graphic or uses an unusual font type, our editor covers the line instead of deleting it and tells you so when you save; tick "Remove covered content for real" to make sure the old text is gone.

Cover and retype

To change a word or number, draw a white rectangle over it and type the new text on top in a similar font and size. On coloured backgrounds or with unusual fonts the patch may show, so zoom in before saving. It only hides the old text, which matters, as explained below.

Fill form fields

Many official forms have interactive fields (an AcroForm). Click, type, tick and save; most browsers and free readers support this. Some older forms use a format called XFA that many readers cannot display; if a form asks for Adobe Reader, open it there. If a form has no fields, place text boxes on the lines instead.

Convert to Word, edit, convert back

To rewrite whole paragraphs, use PDF to Word. A converter has to rebuild paragraphs, columns and tables from positioned characters, so check line breaks, table borders, spacing and fonts afterwards. Our converter has an editable mode and an exact-layout mode; exact layout keeps the look but stores each page as an image, so it is not editable. When you are done, save the document as a PDF again from your office suite.

Edit the original file if you have it

If the PDF was exported from Word, Google Docs, Excel or a design program, editing that source and exporting a fresh PDF beats every workaround: fonts, links, accessibility tags and layout all stay correct. Ask the sender for the original first.

Whiteout is not redaction

This mistake causes real data leaks. A white box or black bar only covers text visually. The characters remain in the page, so anyone can select, copy, search or extract them.

To really remove information:

• Use a proper redaction feature. Dedicated redaction tools, such as the one in Adobe Acrobat Pro, delete the underlying text and image data in the marked area. Many can also remove hidden data such as metadata, comments and attachments.
• Or flatten the pages to images. In our Edit PDF tool, cover the information with whiteout and tick "Remove covered content for real" before saving: every page with whiteout becomes an image with the white areas painted in. With other editors you can do the same by hand, for example with PDF to JPG followed by JPG to PDF. The new file contains only what was visible, but its text can no longer be selected or searched and it may be larger; Compress PDF can shrink it again.
• Or remove it at the source and export a new PDF.

Then check: press Ctrl+A (Cmd+A on a Mac), copy the page into a plain text editor, search the PDF for the hidden word, and look at the document properties for names in the author or title fields. If the text turns up anywhere, it is not redacted.

Signing a PDF: electronic vs digital signatures

• Simple electronic signature. You draw your signature, type your name in a handwriting-style font, or insert a photo of your signature, and place it on the page. It shows an intention to sign. On its own it does not prove who signed, and the document could later be edited without an obvious trace.
• Certificate-based digital signature. The PDF is signed cryptographically with a private key tied to a certificate from a certificate authority, often held on a smart card, token or signing service. Readers can check who signed, whether the certificate was valid, and whether the document changed after signing. EU qualified electronic signatures are a stricter form of this.

A browser tool that places a drawn or typed signature creates the first kind, which is what most everyday paperwork needs: a rental application, a permission slip or a client contract you were asked to "sign and send back". One caution: if a PDF already carries a certificate-based signature, editing it afterwards, even to add your drawn signature, can make that signature show as invalid. Ask the sender how they want you to sign.

Are electronic signatures legally valid?

In many countries, generally yes, with exceptions. Many countries have similar laws to those below, with different details. This is general information, not legal advice.

• European Union: the eIDAS Regulation (EU) No 910/2014 says an electronic signature must not be denied legal effect or refused as evidence solely because it is electronic. Only a qualified electronic signature automatically has the same effect as a handwritten one.
• United States: the federal ESIGN Act and the Uniform Electronic Transactions Act (UETA), adopted by most states, generally give electronic signatures the same legal effect as paper ones where the parties agree to deal electronically. ESIGN excludes some documents, such as wills and certain family-law and court papers.

Depending on the country, wills, property deeds, powers of attorney, some court filings and documents that must be notarised or witnessed may need more than a drawn signature. For anything with serious consequences, ask the recipient what they accept or check with a lawyer.

Privacy: where does your file go?

Many free online PDF editors upload your file, process it on their servers and let you download the result. Contracts, tax forms, passports and medical records deserve more care. Before uploading, check:

• Does the file leave your device? Browser-based tools, such as ours, process the PDF on your computer or phone. A rough test: load the tool, go offline, and see whether it still works (some tools must download their components first).
• How long is it kept? An upload service's privacy policy should say when files are deleted and whether they are used for anything else.
• Who runs it, and does it need an account? That decides which data protection laws apply and whether your documents end up in a stored history.

Keep an unedited copy of the original, and for sending, see how to password protect PDF and Office files.

Editing scanned PDFs

If you cannot select any text, the PDF is almost certainly a scan. You can either use the editor's text tool to cover and retype or add text on top, which is quick for scanned forms, or get the text out first: convert the pages with PDF to JPG, then run them through Image to Text (OCR) and paste the result into a new document. OCR makes mistakes with poor scans and handwriting, so proofread names and numbers. For cleaner scans, see how to scan a document to PDF.

How to edit a PDF with our free tool

1. Open Edit PDF and choose your file. It opens in your browser and is not uploaded.
2. Pick a tool: Edit text to change the document's own words, or text, image, shape, drawing or whiteout to add things on top.
3. Click the page to place it, then move or resize it until it lines up.
4. Save and download the edited PDF, then open it in another reader to check it.

Button names may change, but the flow stays the same. To combine the result with other files, use Merge PDF.

How to sign a PDF

1. Open Sign PDF and choose the document.
2. Draw your signature, type your name, or upload a picture of your handwritten signature (dark pen on white paper, in good light).
3. Place it on the signature line and resize it to fit.
4. Add the date and your printed name or initials if the document asks for them.
5. Save the signed PDF, send it, and keep a copy.

If the file is too large to email, run it through Compress PDF and check that the signature is still sharp.

Frequently asked questions

Can I edit the existing text in a PDF for free?

For words, numbers and single lines, yes: in our Edit PDF tool choose Edit text, click the line and type. The line is retyped in the closest standard font and does not reflow onto the next line. For rewriting paragraphs, convert the PDF to Word and save it as a PDF again, or edit the original source file.

Why does my edited text look different from the rest of the document?

PDFs usually embed only the characters they use, so an editor often cannot reuse the original font for new words and substitutes a similar one. A close match in size and weight hides the difference best.

Is putting a black box over text enough to hide it?

No. The text underneath usually remains and can be copied or searched. Use a real redaction tool or flatten the pages to images, then test by copying the page into a text editor.

Is a drawn signature on a PDF legally binding?

In many countries a simple electronic signature is recognised for most everyday agreements, under laws such as the EU eIDAS Regulation and the US ESIGN Act and UETA. Wills, deeds and notarised papers often need other formalities. This is not legal advice; ask the recipient or a lawyer about important documents.

Why can't I select or edit any text in my PDF?

It is probably a scan, so each page is an image: add text on top or use OCR. If the text exists but editing is blocked, the file may have permission restrictions.

Is it safe to edit confidential PDFs online?

It depends where the processing happens. Browser-based tools keep the file on your device; upload services store it on their servers, at least temporarily. Read the privacy policy before uploading contracts, IDs or medical forms.