You do not need Adobe Acrobat, a subscription, or any download to work with PDFs on a Mac. Preview — the app that already opens every PDF and image — is a genuinely capable PDF editor hiding in plain sight. It can annotate, sign, merge, rotate, reorder and delete pages, fill out forms, shrink file size, and lock a file with a password. This guide walks through each one, in the order most people actually need them.
Open the Markup toolbar (this is where everything lives)
Open any PDF in Preview (double-click it — Preview is the default). The editing tools live behind one button: click the Markup icon (the pen-tip in a circle) near the top-right, or choose View > Show Markup Toolbar. A strip of tools appears: selection, sketch, shapes, text, signature, and a color/thickness picker. Nothing you do is saved until you press Command-S, so experiment freely.
Annotate: add text, highlights, arrows, and shapes
With the Markup toolbar open:
- Add a text box — click the Text (T) button, then drag the box where you want it. Change font and size from the A font button.
- Highlight — click the highlighter button, then drag across the words. Click the small arrow beside it to switch colors or switch to underline/strikethrough.
- Draw arrows, boxes, and circles — use the Shapes button. Drag the blue handles to resize; drag the green handle on an arrow to bend it.
- Sketch freehand — the Sketch tool cleans up shaky lines into neat shapes automatically.
Sign a PDF without printing it
Preview stores a reusable signature so you never have to print, sign, and re-scan a document again.
- Click the Signature button in the Markup toolbar, then Create Signature.
- Choose Trackpad (sign with your finger), Camera (sign a white piece of paper and hold it to the webcam), or iPhone (sign on your phone screen).
- Your saved signature now drops onto any PDF — click it, then drag and resize it over the signature line.
The signature is saved for next time, so recurring forms take seconds.
Fill out a PDF form
If a PDF has real form fields, just click a field and type — Preview handles interactive forms directly. If it is a flat scan with no clickable fields, use the Text tool to drop text on top of each blank line, and the signature tool for the signature. Either way, save with Command-S when done.
Merge (combine) two or more PDFs into one
Open the first PDF, then choose View > Thumbnails to show the page sidebar.
- Drag a second PDF file (from Finder or the desktop) directly into the thumbnail sidebar — it appends those pages.
- Or open both PDFs and drag pages from one thumbnail sidebar into the other.
- Drop pages exactly where you want them in the sequence, then File > Export as PDF to save the combined file.
This is the fastest free way to combine invoices, scanned pages, or a multi-part contract.
Delete, reorder, and rotate pages
All page management happens in the same Thumbnails sidebar (View > Thumbnails):
- Delete a page — click its thumbnail and press Delete.
- Reorder pages — drag a thumbnail up or down.
- Rotate a page — select the thumbnail and press Command-R (right) or Command-L (left), or use Tools > Rotate. Select several thumbnails first to rotate them all at once.
Compress: shrink a PDF that is too big to email
Large scans often exceed email limits. To shrink one:
- Choose File > Export.
- In the Quartz Filter menu, pick Reduce File Size.
- Save. The new file is dramatically smaller — check it still looks sharp, and keep the original if you need full resolution.
If Reduce File Size makes it too blurry, there are free custom Quartz filters online that compress less aggressively, but the built-in one is fine for most everyday documents.
Password-protect a PDF
Choose File > Export, tick Encrypt, and set a password. Anyone opening the file will need it. Store the password somewhere safe — there is no recovery if you forget it.
Why this matters if you are shopping for a Mac
Every one of these features is built into macOS at no cost — a refurbished MacBook does the same PDF work as a brand-new one, no software to add. If you are pricing out a Mac for paperwork-heavy work, our Apple clearance models handle Preview, signatures, and everything above without breaking a sweat.
Related guides
- How to print (save) anything as a PDF on a Mac
- How to scan a document on a MacBook
- How to zip and unzip files on Mac
Frequently Asked Questions
Can Preview really edit PDFs, or just view them?
It genuinely edits them. Preview can annotate, sign, merge, rotate, delete and reorder pages, fill forms, compress, and password-protect a PDF — all without Adobe Acrobat or any subscription.
Can I edit the actual text inside a PDF with Preview?
No — Preview cannot rewrite the original body text of a PDF (that requires Acrobat Pro or a converter). It layers new text, shapes, and signatures on top, which covers the vast majority of everyday edits.
How do I combine two PDFs on a Mac for free?
Open one in Preview, show the Thumbnails sidebar (View > Thumbnails), drag the second PDF into that sidebar to append its pages, then File > Export as PDF.
How do I shrink a PDF so I can email it?
File > Export, then choose Reduce File Size from the Quartz Filter menu and save. Keep the original if you need full resolution.
Do my edits change the original file?
Only when you save (Command-S) or export. Until then nothing is written, so you can experiment freely — and Export lets you keep the original untouched by saving a copy.