Edit PDF

What you can do to a page

Change the words that are already there. Pick Edit text, click a line, and retype it. The line comes back in its own place, in its own size, in the colour it was written in, and the paper behind it keeps its colour too. Empty a line completely to take it off the page.

Text, typed straight onto the page in the size and colour you choose. This is how a form gets filled in when the form has no fields in it - which is most forms, because most of them are scans of paper.

A picture: a logo, a stamp, a screenshot. Place it, then drag the corner to size it.

A white patch, which hides whatever is under it.

To sign, use Sign PDF. To highlight, draw, or add boxes, arrows and comments, use Annotate PDF.

1. Drop the PDF on the box at the top and wait for the first page to be drawn.
2. Edit text is already chosen. Every line the page holds lights up as you pass over it; click one and retype it.
3. To add something, pick Text, White out or Image from the row.
4. Text is placed with a click and then typed. A white patch is drawn by holding the mouse down and dragging. A picture is chosen, then placed with a click.
5. Switch to Move to drag anything you have added, or to pull the corner of a patch or a picture. Double click a line of text to retype it.
6. Use Back and Next under the page to work on the other pages. Everything you add is remembered, page by page.
7. Press Save the PDF. Every mark on every page is written into the document at once.

How changing the text works, and what it will not do

A PDF does not hold a sentence you can edit. It holds instructions to draw particular letters at particular places. So this reads those instructions, finds where each line sits and how tall its letters are, samples the colour of the ink and of the paper behind it, covers the old line in the paper colour and draws your line in its place. That is the same thing a print shop has always done, done by the computer instead of by hand, and the file it saves is an ordinary PDF that looks and prints exactly as you see it.

Because of that, three things are worth knowing before you start. A line does not reflow: the lines under it do not move, so a sentence much longer than the one it replaces is shrunk to fit its own line rather than pushing the page about. A font with real character comes back as its nearest plain cousin, because the only fonts every PDF reader is guaranteed to have are Helvetica, Times and Courier. And the old letters are covered rather than taken out of the file, so somebody who copies the text out of the page can still find them - fine for a typo, not good enough for a secret.

It cannot read a scanned page. A scan is a photograph, so the words in it are not words to a computer, and there is nothing for Edit text to pick up. You can still type on it and cover parts of it with a white patch. To make its words editable, run it through OCR PDF first.

Filling existing form fields is not here yet. If a document has real fields, your PDF reader fills them better than any website can. For everything else, typing onto the page works and looks the same when printed.

A white patch is not redaction

A white rectangle covers what is underneath in every reader, and it is genuinely opaque. For hiding a phone number before you send a scan on, it does the job.

On a page that holds real text rather than a scan, understand what you have: the letters are still in the file, underneath the patch, and somebody who copies the text out of the page would get them. If a document has to be redacted properly, remove the whole page with Delete pages, or turn the pages into pictures with PDF to JPG and rebuild the document from those with JPG to PDF. That destroys the text, which is the point.