Redact Text and Images In PDFs Using Preview

You can permanently and securely remove text and images from PDF documents with the Preview app on your Mac. This can be used to hide information from the next person to view the PDF, or to simply reduce the size of the file.
You can also watch this video at YouTube (but with ads).
Video Transcript: Hi, this is Gary with MacMost.com. Let me show you how to redact information in a PDF file using Preview on your Mac. 
MacMost is brought to you thanks to a great group of more than 2000 supporters. Go to MacMost.com/Patreon. There you could read more about it. Join us and get exclusive content and course discounts. 
So if you have a PDF, whether it is one you have created or one that somebody gave to you, and you want to redact information in it, meaning you want to get rid of that information. You want to take it out so nobody could actually see it. There is a tool to do that in the Preview App. The Preview App is the default app for viewing and working with PDF's in macOS. 
So I've got a PDF document here (example.pdf) and if I double-click on it and it will open up in Preview. But before I do that since I'm going to redact information in it and get rid of that information I want to make a copy of it because I want the original to stick around for my own use. But when I pass it onto somebody else I want them to not be able to see somethings in the document. So I'm going to select it. I can choose File, and then Duplicate or Command D. This will create another copy of it and this copies the one I'm going to use to redact information. So I can rename it as I see fit. I'm going to double-click on it and it will open up in Preview. 
Now that it is in Preview you could see maybe there's something in it that you want to get rid of. Now the wrong way to go about doing this is to do what you may have done in the past which is to use the Markup Tools here. Then use a shape, like let's say a rectangle shape, and then take that rectangle and place it over what you want to eliminate. Then it looks like it's gone. If I were to save this and somebody else were to open it up they wouldn't be able to see the information behind it. But, actually that information is still there even if they don't have a tool that can be used to remove this element the information is still in the file so it has not been securely removed. Now this technique still has some good uses. For instance, I can go in here and let's change the color of the rectangle to white and have no border around it. Now it creates this white area here. Now if I'm printing this document and handing somebody a printout this works perfectly fine. The information is not going to be in the printout. Another use for this, of course, is that it's not going to use any ink so if you're printing this for your own use and you want to save printer ink you can use rectangles like this. I'll even Option Drag and create another rectangle and get rid of this image to save more ink. You can continue to use this and do a printout and it works perfectly well. 
Except that when you give this PDF file to somebody else they can get to all this information that's behind these rectangles. So what you want to do instead to really secure and rid of that information is to use the Redact Tool. Now just like with putting a shape you want to use this Markup Tool. So you want to go into Markup and then instead of choosing a shape you want to go over to this tool here which is the Redact Tool. You want to select it and you're going to get a warning when you select it telling you that the contents could be permanently removed. If you use this Tool often you probably want to check this box and then not have to deal with the warning in the future. 
Now when you use the Redact Tool you'll notice the pointer changes to either crosshairs or to a text pointer where I can select text. So if you're over text obviously it's like this and you may think that the way it works is you can select text and then maybe hit delete or some other key to redact it. But in fact it just redacts the text right away. So, for instance, I could go ahead here and just select this text. You can see how it redacts it. It puts a black box with these x's over it right where the text is. I can continue to select more text if I want. So I can keep selecting text like this and just go throughout the document and select more and more. In fact it is okay to select entire paragraphs. You just keep going like this. Now I can still move the pointer around like this to adjust. But when I release it's then going to stick to that. 
If I move my pointer over it you can see how it shows me what is underneath. But it shows that it is redacted. Redaction isn't actually going to happen until you Save. In the meantime you could select and unredact certain things if you want. The Undo feature works with this as well. So, if I do Command Z here you can see how it undoes the last thing I did. Command Z undoes the thing before that etc. 
Now a useful tip here is you can use Edit and then Find with this and it will work. I can actually search for something, like this, and you could see it is going to show me where that is. It's not going to affect Redacting but it does help me find things. So now on top of that I can redact as much as I want and you can see the search remains there. So I can keep going with redaction. 
Now what about when the cursor is a crosshairs, like that. Well that can be used to redact an area. It is very useful for images. So here I've got an image and I can select an area in that image, like this, and redact it. I can even select another area and redact that as well. I can also just redact over an entire larger area like this. As long as the Redaction Tool is selected and I see a crosshairs here I can redact sections. That's true for text as well. So notice here as I more the pointer over the text inbetween lines it changes to little crosshairs there. So I can drag a rectangle, like that, over an area and it will redact the text under it. Notice that I can move over these areas and see what is underneath if I want. I can even drag these areas around to adjust them and drag the edges here to adjust the size as well. Then if I have one selected a Delete will get rid of the redaction area. 
So now that I have everything redacted like I want I can Save this. All you need to do is just Save. Now while it is still open you can still continue to Edit it. But once I close it redactions are permanent. So now if I were to open up this document again you could see moving the pointer over these areas does not reveal what is there and I can't do anything to affect these redacted areas. That information has been permanently removed. It is not part of the file anymore. That's why it is pretty important to make a duplicate of this if it is your only copy of the PDF. Obviously if you are producing something, say in Pages or Word, you export as PDF and then you use Preview to redact you could always go back to the Pages or Word document to create another version of the PDF. But if the PDF is all you've got, like it's a document that somebody gave to you and you don't have the original, then you want to make sure you duplicate it before you start redacting things. 
Now I want to show you something that demonstrates how the information is really gone but also can be particularly useful.  Let's go and take the original document. I'm going to make another copy of it and I'm going to open that one up. Now let's say I want to shrink this PDF down. It's too big and the reason it is probably too big is not this text here, it's probably the image. So what I'm going to do is if I go in and create a shape, like a rectangle, and just make it a white shape and then blank out this image, like that, I would think that now that image isn't there. Sure enough if I printout it's not going to be there. It's going to save me a lot of ink. But if I Save and then I take a look at the original I can see the original is 268K and the copy with that image blanked out is still that size! In fact it is a little bit larger because I added a box to it. If I were to open it up I can see I can select the box there and get rid of it and the image is still there. So I haven't really shrunk the file at all. It's not a big deal. 268K. But imagine if this was 500MB or something. There was a bunch of images you really didn't need in it. 
But redacting actually deletes the data. So let's try that instead. If I use the Redaction Tool and then I redact this. Save. I'll just use Command S there. Then Close. Now if I take a look at this document I can see it's only 66K. It really did get rid of the image and shrink the file. Now if you'd rather not see this black box there you can actually go into the document again and then go into Markup Tools and then add a white box as a shape. Put it over the redacted area like that. I'll Save and now I can look and I can see it's slightly bigger because I added that white box but it's now a white box. It looks a little neater and it prints out okay and it maybe useful in that it hides the fact that something has been redacted. 
So that's how you can Redact information from PDF's using just the Preview App that's already on your Mac. I hope you found this useful. Thanks for watching.
Comments: 3 Responses to “Redact Text and Images In PDFs Using Preview”

Sheldon
3 months ago
Thanks bunches
Gene
Great video. Will come in handy in the future.
MelH
2 months ago
Thanks! I actually learned THREE things from this!
Redact Text and Images In PDFs Using Preview

Comments: 3 Responses to “Redact Text and Images In PDFs Using Preview”

Leave a New Comment Related to "Redact Text and Images In PDFs Using Preview"

Welcome to MacMost

Free Weekly Newsletter

MacMost Online Courses

Keyboard Shortcuts PDF

Connect with MacMost

MacMost Sections

Popular Tutorials

Information
