Attachment Preview support
Attachment Preview adds a Preview button to PDF and image attachments in Gmail, and an Open in new tab button to other attachments. In compose, reply and forward, Gmail downloads when you click an attachment chip; Preview lets you check a PDF or image without downloading.
How to use it
- Open Gmail at mail.google.com in Chrome.
- Open an email with an attachment, or attach a file in a new message, reply or forward.
- Click Preview under a PDF or image. It opens in a viewer on top of Gmail (overlay, page counter).
- Press Esc or click the close button to go back.
- For any other file, click Open in new tab.
What each file type does
| File type | What happens |
|---|---|
| Opens in the built-in viewer inside Gmail. Scroll all pages; page counter; select and copy text. | |
| PNG, JPG, GIF, WebP images | Open in the same viewer, sized to fit your screen. |
| Text and other types Chrome can display | Open in a new tab, without downloading. |
| Word, Excel, PowerPoint, ZIP and other types Chrome cannot display | Chrome downloads them from the new tab. In a received email, click the attachment card to use Gmail's own viewer for Word or Excel (and for HEIC, which Gmail previews natively). |
Where it works
- Gmail on the web (mail.google.com) in Chrome on Windows, Mac and Chromebook.
- Opened emails, plus compose, reply and forward.
- Not the Gmail apps for iPhone, iPad or Android.
The Preview button is missing
- Reload Gmail (Ctrl+R, or Cmd+R on a Mac). Gmail sometimes updates its page in the background.
- Check the extension is on: go to chrome://extensions and make sure Attachment Preview is enabled.
- After the 1.1 update, Chrome may turn the extension off until you approve its new access to mail-attachment.googleusercontent.com (the Google address Gmail uses for attachment files). Open chrome://extensions, find Attachment Preview and accept the request.
- Check the file type: PDFs and images get Preview; everything else gets Open in new tab.
- Still missing? Email us with your Chrome version (chrome://version) and whether it happens in an opened email or in compose.
The preview shows an error
- Very large PDFs (over 50 MB) are not previewed; download those instead.
- Try reloading Gmail and opening the email again.
Password-protected PDFs
Gmail's native viewer prompts for a password on protected PDFs. In version 1.1 and later, Attachment Preview does too, inside the overlay so you stay in the thread: you see an inline Password form with an Open button. A wrong password shows Incorrect password, try again. The password is used only to open that file and is never stored, logged or transmitted.
Adobe Acrobat opens PDFs instead of Gmail
With Adobe Acrobat for Chrome installed, Gmail's native PDF click opens a chrome-extension:// tab. Attachment Preview's Preview button still opens normally. To stop Acrobat taking over Gmail's own click:
- Click the puzzle icon in Chrome's toolbar.
- Click Adobe Acrobat, then the three-dot menu, then Options.
- On Adobe Acrobat preferences > General, under Open PDFs in Acrobat from your browser, uncheck Gmail.
- Reload Gmail.
Online PDFs and Google Drive have separate checkboxes on that screen.
Privacy
The extension collects nothing and sends nothing anywhere. Attachments are shown only in your browser. For password-protected PDFs (version 1.1 and later), the password is used only to open that file and is never stored, logged or transmitted. It keeps one small counter in the extension's own local storage on your device so it can ask once whether you would like to rate it. That counter is never sent anywhere and is deleted when you remove the extension. Full details: Privacy Policy.
Contact us
Bugs, questions or ideas. We read every message.