PDFpenPro is a standout for Mac users thanks to its solid features, including an excellent OCR engine.
Acrobat Pro DC
Acrobat Pro DC offers a complete set of PDF-editing tools, and it even lets you edit scanned documents.
PDFescape is a basic, web-based PDF-editing and -annotation program you can use for free.
PDF files are generally intractable entities, designed to be read and to retain the kinds of good design and page layout that you expect from printed media, such as magazines and newspapers. But with a good PDF editor, you can make changes to the unchangeable, with tools that recognize text in scanned documents and let you edit text and images. And PDF-annotation tools let you mark up and make notes on files so that someone else can update the original.
When you need to edit PDFs, the best editor is SmileOnMyMac's PDFpenPro 11, at least on the Mac, thanks to its host of features and outstanding capabilities in optical character recognition (OCR). Windows users (or Mac users considering an alternative) should turn to Adobe Acrobat Pro DC, which also boasts an impressive tool set. As for PDF annotation, Mac users don't need to look any further than the Preview app that's built in to macOS; otherwise, your best bet is PDFescape, an easy-to-use app that's free when you're annotating smaller documents.
Here's what we think of the various desktop options for editing and annotating PDFs.
Best PDF editor
PDFpenPro is a macOS-only PDF editor that's been available for the Mac for many years. It's also available in a less expensive version with fewer editing options. (That version, PDFpen is available for the Mac as well iOS devices.)
PDFpenPro is a standout for Mac users thanks to its solid features, not the least of which is an excellent OCR engine. With full PDF-document editing, you can make changes to text and replace images in PDF documents. Additionally, you can create PDFs from scratch, create or edit forms, and create tables of contents for your PDF documents.
The application's OCR tools are rock solid. When you open an existing PDF file in PDFpenPro, the application automatically detects whether the document you're working with is a scanned image or already contains selectable text. If it's the former, the application asks whether you want it to recognize the text on the page. Even with large documents topping 400 pages, PDFpenPro handled text recognition seamlessly in a matter of minutes, making the text searchable and editable. That said, editing recognized text is not as easy as editing text in a nonscanned document.
Best PDF editor on Windows
You'd expect Adobe Acrobat Pro DC to be great because it comes from Adobe, the birthplace of the portable document format. (Yup, that's what PDF stands for.) And to some extent, this full-service PDF-editing application meets that expectation.
Acrobat Pro DC offers a complete set of PDF-editing tools, and it even lets you edit scanned documents. Acrobat DC's OCR engine can convert scanned documents to text, which you can then search through and change. But Acrobat doesn't offer to convert an entire document the moment you open it; instead, the app waits for you to begin using the Pro DC's edit tools, recognizing and converting the pages as you select them for editing. Changing text in an OCR'd document was simple, and the results looked great.
It's also easy to edit images and text in documents you haven't scanned. I was able to make changes to everything with zero issues.
What I don't like about Acrobat Pro DC is the interface. It feels like a half-realized demo of what the app could be. Editing tools surround your document, and the UI feels disorganized, offering few options for customization. Because it's designed to work on both Macs and PCs, Acrobat Pro DC looks like it belongs in neither environment. This doesn't make this program bad at what it's supposed to do; it just makes you feel like you're working outside your chosen OS.
Best PDF-annotation tool
PDFescape is a basic, web-based PDF-editing and -annotation program you can use for free to work on PDF documents that are smaller than either 10MB or 50 pages (whichever is greater). If you need to edit larger files, you can get the paid account for $36 a year.
Accessible through any modern web browser, PDFescape offers no OCR capabilities. But its annotation tools are easy to use. You'll find a pretty solid set of standard annotation tools that can easily add, highlight and strike through text; insert notes; and otherwise mark up the pages of your PDF file. Using the web app's insert tools, you can also add new images and text to a document, white-out text, and add web links and form fields.
PDFescape does have some major limitations in adding new text. Because there are no OCR capabilities, you can't make changes to existing text; you're limited to adding new text to an existing document. Additionally, the app has very limited font options, as it doesn't use any of your computer's fonts. So you're limited to Arial, Courier New, Times New Roman, Verdana and a Signature font for signing documents.
Built-in PDF annotation for macOS
Apple's Preview app is built-in to the macOS and offers a minimalist but valuable set of tools for marking up any PDF file. You won't find full-on PDF editing here. But if you need a basic set of tools for highlighting or redacting text, making notes, or adding comments to a document, you won't likely need much more than what's already available on your Mac.
Preview's markup tools are hidden when you first open a PDF document. To see them, you'll have to look for the small pencil icon that appears near the Spotlight search bar at the top of your PDF document's toolbar. Clicking this reveals a small set of tools you can use to select text and add objects, text or notes to your document.
The app's standout feature is a signature tool you can use to store a signature you create using your trackpad or scan using your Mac's iSight camera. You can then easily add that signature to a document by clicking Preview's Signature tool. Simple and easy to use once you set it up, Preview's signing feature will prove its usefulness every time a digital document requires your John Hancock.
One final note for macOS Mojave users: You can access all of Preview's editing tools without opening Preview. Just use QuickLook to view a PDF, then turn to the Markup button in that mode.
PDF editor with the cleanest interface
Readdle's macOS-only PDF Expert is a popular PDF-editing tool that allows you to make changes to text in existing PDF documents, including by removing and replacing images, updating text, and adding text of your own. PDF Expert lacks OCR capabilities, so if you want to edit text in scanned documents, you'll need to look beyond this program.
Of all the apps I tested, PDF Expert has the cleanest interface and therefore was the most pleasant to use. Two tabs appear at the top of the screen: Annotate and Edit. Clicking one of them gives you an appropriate selection of tools to perform either annotation or editing tasks.
PDF Expert's editing tools are flawless. Click text in your PDF, and tools for editing text will slide out so you can make changes. Select an image, and tools for changing the image appear. You can move selected text anywhere on the page you want or remove it altogether.
PDF Expert struggles with large documents; otherwise, this would have been my top pick for both macOS and Windows. But every time I attempted to open my nearly 450-page test file, PDF Expert hung. Until this program behaves more dependably, look elsewhere if you tend to work with larger documents.
PDF editor with some quirks
Wondershare's PDFelement Pro is a full-featured PDF editor with an OCR engine for recognizing scanned text and a standard set of tools. With those, you can fill in forms, annotate documents, create and add signatures, and edit images within a document.
PDFelement had no problem opening anything I threw at it, including scanned documents, large files and image-heavy PDFs. Once documents are open, PDFelement Pro offers a fairly simple interface, with a set of tools on the left side of your document that are easy to figure out. Just select a tool, and you can go to work making changes to the file.
Editing images, adding signatures and using annotations in the application all worked as planned, but I did experience some odd behaviors when I was editing or adding text using PDFelement Pro. In particular, when I was editing existing text in a document, the application wanted to make the text bold and would not allow me to change the content back to regular text. Also, when I added new text boxes, my own text did not display normally; the program always added a space after I typed an apostrophe. And the program constantly played my Mac's system beep as I typed. That's both annoying and not optimal.
Too many limitations
Sejda is a web-based PDF-editing application that works on any OS that has a modern web browser. A desktop version converts that web interface into something that runs on your computer. You can use a free version of Sejda, but it limits the number of daily tasks you can perform and the size of the documents you can access.
Sejda has no OCR engine, so you can't use this app to edit PDF files created from scanned documents. You can edit only PDF files that already have selectable text.
To edit your PDF file, you upload it to the Sejda website and then use the toolbar at the top of the page to choose your tools. You'll find tools for editing text, adding links, adding form fields and images, and signing or annotating your document. All of Sejda's tools are rudimentary at best. The app breaks every line of text in your document into a single text entry, so you can't edit entire paragraphs of text. When you do edit existing text, remnants of the previous text often get left behind in the document. Sejda will let you add new images to a document, but you can't use the app to edit or remove existing images.
Sejda isn't a great app, but it works in a pinch when you need to make a quick change to an existing PDF document and you have no other tools at hand.
How we test PDF editors
We look at both PDF editors and PDF-annotation applications. Every PDF editor can also annotate documents, but dedicated PDF-annotation tools aren't designed to make changes to any of the original context in a PDF document.
While testing each of these applications, I used a few different types of documents, including large, text-heavy files; documents with a mix of formatted images and text; and simple documents with text and images inserted into the document in a linear fashion. I tested features like text recognition (when that was supported), and I tried making changes to text, replacing and adding images, and adding annotations.