Merge PDF

Use Preview to combine PDFs on your Mac

Learn how to combine PDFs and reorder, rotate, and delete pages.

Combine two PDFs

1. Open a PDF in Preview.
2. Choose View > Thumbnails to show page thumbnails in the sidebar.
3. To indicate where to insert the other document, select a page thumbnail. 
4. Choose Edit > Insert > Page from File.
5. Select the PDF that you want to add, then click Open. 
6. To save, choose File > Export.

Combine part of a PDF with another PDF

1. Open the PDFs that you want to combine in Preview.
2. In each document, choose View > Thumbnails to show page thumbnails in the sidebar.
3. Press and hold the Command key, select the page thumbnails that you want to add to the other document, then let go of Command. 
4. Drag the selected thumbnails into the sidebar of the other PDF, then release where you want them to appear. If your Mac has macOS Sierra or earlier, drag the thumbnails directly onto a thumbnail in the other PDF.
5. To save, choose File > Export. 

Rotate, delete, and reorder pages

1. Open a PDF in Preview.
2. Choose View > Thumbnails to show page thumbnails in the sidebar.
   • Rotate a page: Select a page thumbnail, then choose Tools > Rotate Left or Rotate Right.
   • Delete a page: Select a page thumbnail, then choose Edit > Delete.
   • Reorder pages: Drag a page thumbnail to a new location in the sidebar.

Learn more

Learn how to mark up PDFs and edit photos in Preview.

Published Date: Nov 1, 2017

High Sierra Merge PDFs

Combine PDFs

Combine all or part of two or more PDFs into a single PDF.

WARNING: Changes you make to a Preview document are saved automatically. If you want to keep the original PDFs (in addition to the new combined one), choose File > Duplicate to create a copy of each PDF before combining them.

1. Open the PDFs you want to combine.
2. In each open PDF, choose View > Thumbnails to display the page thumbnails in the sidebar.
3. Drag the thumbnails you want to add (Command-click to select nonadjacent pages) to the thumbnail sidebar in the other PDF.

You can add pages to the end of the document or between pages in a document. Drag thumbnails to reorder them.

Tip: To add an entire PDF to the beginning or end of another PDF, drag the PDF icon in the Finder to the sidebar of an open document.

Twitter Password Concerm

Keeping your account secure

By ‎@paraga‎Thursday, 3 May 2018    

When you set a password for your Twitter account, we use technology that masks it so no one at the company can see it. We recently identified a bug that stored passwords unmasked in an internal log. We have fixed the bug, and our investigation shows no indication of breach or misuse by anyone.

Out of an abundance of caution, we ask that you consider changing your password on all services where you’ve used this password. You can change your Twitter password anytime by going to the password settings page.

About The Bug

We mask passwords through a process called hashing using a function known as bcrypt, which replaces the actual password with a random set of numbers and letters that are stored in Twitter’s system. This allows our systems to validate your account credentials without revealing your password. This is an industry standard.  

Due to a bug, passwords were written to an internal log before completing the hashing process. We found this error ourselves, removed the passwords, and are implementing plans to prevent this bug from happening again.

Tips on Account Security

Again, although we have no reason to believe password information ever left Twitter’s systems or was misused by anyone, there are a few steps you can take to help us keep your account safe:

1. Change your password on Twitter and on any other service where you may have used the same password.
2. Use a strong password that you don’t reuse on other websites.
3. Enable login verification, also known as two factor authentication. This is the single best action you can take to increase your account security.
4. Use a password manager to make sure you’re using strong, unique passwords everywhere.

We are very sorry this happened. We recognize and appreciate the trust you place in us, and are committed to earning that trust every day.

Chrome Feedback

1. On your computer, open Chrome.
2. At the top right, click More .
3. Click Help Report an issue.
4. Add details, including steps to help us recreate the issue you're experiencing.
5. Choose if you want to include more information in your report, like a web address, your email address, or a screenshot.
6. To submit the report, click Send.

We appreciate your help! We probably won't be able to send you an individual response, but we'll investigate your report and use the information you provide to improve Google Chrome.