Preview on Mac can annotate, sign, and fill forms in your PDFs, but it cannot directly edit the original embedded text.
The short answer to how to edit a PDF in Preview is that you can add text boxes, highlight passages, insert your signature, and rearrange pages—but you cannot rewrite the words already printed on the page. Preview treats every change as a separate markup layer on top of the original document. This makes it perfect for filling out forms and leaving review notes, but you will need a dedicated editor like Adobe Acrobat if you want to change the source text itself. This guide walks through every real editing task Preview handles, and how to do them step by step.
What Editing Can You Actually Do in Preview?
Preview handles most surface-level edits and page organization with ease. The table below separates what the built-in app can do from what requires a third-party tool, so you know exactly when Preview is enough and when to switch.
| Task | Available in Preview? | Details |
|---|---|---|
| Add text boxes | Yes | Adds a floating text box over the page content. |
| Highlight, underline, strikethrough | Yes | Applies directly to the existing text on the page. |
| Insert a signature | Yes | Create one using your trackpad and drag it into place. |
| Reorder or delete pages | Yes | Drag pages in the thumbnail sidebar or press Delete. |
| Draw or add shapes | Yes | Sketch freehand or insert lines, arrows, and speech bubbles. |
| Fill out interactive forms | Yes | Text boxes automatically link to form fields. |
| Flatten annotations | Yes | Use the Print to PDF method to lock edits in place. |
| Edit original embedded text | No | Requires Adobe Acrobat or another dedicated PDF editor. |
| Edit original images in the PDF | No | Preview can crop, but not replace or alter source images. |
How to Open the Markup Toolbar and Add Text
The Markup Toolbar is your control center for every annotation in Preview. Open your PDF, then click the Show Markup Toolbar button (the icon that looks like a pen tip inside a circle). The toolbar appears above your document.
To add text, click the Text tool—it looks like a capital “T” inside a small box. Click anywhere on the PDF, and a text box appears. Type your content, then drag the box to position it. You can change the font, size, and color using the A button in the toolbar while the text box is selected.
How to Reorder or Delete Pages in a PDF
Page organization happens entirely through the thumbnails sidebar. Click View in the menu bar and select Thumbnails, or press ⌘⌥2 on your keyboard. A column of page thumbnails appears on the left side of the Preview window.
- Reorder: Drag any thumbnail up or down in the sidebar. A blue line shows where the page will land.
- Delete: Select the thumbnail you want to remove and press the Delete key on your keyboard, or right-click it and choose Delete Page.
- Insert blank pages: Open the Edit menu and choose Insert to add a blank page after the currently selected thumbnail.
These changes are non-destructive while the file is open—you can undo a deletion immediately using ⌘Z.
How to Add Your Signature to a PDF in Preview
Preview has a built-in signature tool that does not require printing, scanning, or an iPhone. Click the Signature icon in the Markup Toolbar (the icon that looks like a cursive signature). If you already have a saved signature, click it to insert it onto the page. To create a new one, click Create Signature, then use your trackpad to sign with your finger. Once the signature appears on the page, drag it into position and resize it by pulling the corner handles.
Apple’s official Preview annotation guide covers this workflow in more detail, including how to use your iPhone or iPad to capture a signature if you prefer a stylus.
How to Save, Export, or Flatten Your Edited PDF
How you save your PDF determines whether your annotations can be edited later or locked down permanently.
- Keep annotations editable: Choose File > Save or File > Export. The text boxes, highlights, and signatures remain as separate layers that you can modify later.
- Flatten annotations (lock them in place): Choose File > Print, then click the PDF button in the print dialog and select Save as PDF. This bakes all your markups directly into the page image. Once flattened, you cannot move or edit them.
Can You Edit a Password-Protected PDF in Preview?
Preview can open and annotate password-protected PDFs as long as you have the password. However, Preview cannot remove the security restrictions. If the PDF is locked to prevent editing entirely, you will need dedicated editing software to change the permissions or modify the document. Preview respects whatever restrictions the original creator applied.
When to Switch to a Dedicated PDF Editor
Preview covers a solid 80% of everyday PDF tasks for free. But when you need to change the actual content of the document, you have to move to a paid tool.
| Feature | Preview (Free, Built-in) | Adobe Acrobat Pro (Paid) |
|---|---|---|
| Best for | Annotations, signatures, forms | Full text editing, OCR, conversion |
| Edit source text | ❌ | ✅ |
| Edit source images | ❌ | ✅ |
| OCR scanned documents | ❌ | ✅ |
| Convert to Word or Excel | ❌ | ✅ |
| Price | Free with macOS | Subscription |
Use Preview for quick additions, signatures, and page organization—it launches instantly and handles nearly everything a typical reader or form-filler needs. Switch to a dedicated editor only when the task demands rewriting the document’s original text or converting it into another format.
References & Sources
- Apple Support. “Annotate a PDF in Preview on Mac.” Official guide covering the markup toolbar, signatures, and saving options.
- Tom’s Guide. “How to edit a PDF on Mac.” Covers third-party alternatives and workarounds for general PDF editing.
- Apple Communities. “Can I edit PDFs or Preview Docs w/ Mac?” Discusses the limitations of editing original text vs. annotating.