Processed on your computerOutlook PST files, open in your browser.
Read messages and attachments without Outlook.
Browse folders, read messages, and download attachments.
Drop your PST file here
Or choose one file from your computer.
Tested with public ANSI and Unicode PST samples. Compatibility depends on the file’s structure and condition.
Verified on desktop Chromium · 256 MiB is an experimental input limit, not a large-mailbox guarantee.
Your original file stays unchanged.
Choose your file again on your next visit.
How to open a PST file
- 1. Choose a file
Choose a PST file on your computer or drag it to the area above.
- 2. Browse and search
Choose a folder and find messages by subject, sender, recipient, or date.
- 3. Read and download
Select a message to read it and download the attachments you need.
Frequently asked questions
What is a PST file?
PST is a file format Microsoft Outlook uses to store messages and folders. PastBox is a web tool for reading messages in PST files stored on your computer.
Can I open a PST file without installing Outlook?
Yes. Choose one PST file in a desktop browser. It is free to use with no installation or login. Opening files requires JavaScript.
Are my messages or files stored on a server?
No. PST files and messages are processed only in your browser and are never sent to a server. The original file is never modified. Closing a file clears messages and the search index from memory. Choose the file again on your next visit.
What if the message text looks garbled?
First choose Auto-detect under Character encoding. If the text still looks garbled, choose an available encoding that matches the original file. The file will be reread. Unsupported encodings or damaged data may still not display correctly.
Which PST files are supported?
ANSI and Unicode PST files are supported and tested using public ANSI v14 and Unicode v23 samples. The file input limit is 256 MiB; this does not guarantee that all large archives will work. OST, some encryption formats, and damaged-file recovery are not supported.
Which messages and attachments can I view?
You can search subjects, senders, and recipients; filter by date; read HTML, plain text, and RTF converted to text; and download individual attachments. Full-body search and sending mail are not supported. External images and scripts are blocked, so some original formatting may be omitted.