822

.822RFC 822 Message Format

IETF (Internet Engineering Task Force) · 1982

Developer
IETF (Internet Engineering Task Force)
Category
Documents
MIME Type
message/rfc822
First Released
1982
Open Format
Yes
File Signature
Not applicable, as it's a plain text format defined by structure, not a specific byte signature.
At a Glance
.822
RFC 822 Message Format

The .822 file extension signifies a standard format for representing email messages, including headers and body content.

Reviewed on May 18, 2026
Compression
Plain text
Transparency
No
Editability
High
Best for
Standard email messages

Key Features

  • Defines standard email headers like From, To, Subject, Date.
  • Plain text format, readable by humans and machines.
  • Separates message headers from the message body with a blank line.
  • Foundation for subsequent email format standards.

Best For

  • Representing raw email data.
  • Ensuring email compatibility across systems.
  • Archiving email content in a universally readable format.

Less Ideal For

  • Rich text or HTML email content (use MIME instead).
  • Sending binary attachments directly (requires MIME encoding).
  • Modern email features like encryption (use S/MIME or PGP).

Common Use Cases

  • Storing and exchanging email messages.
  • Archiving email communications.
  • Interoperability between different email clients and servers.
  • Parsing and processing email content programmatically.

How to Open It

  1. Most email clients (like Outlook, Thunderbird, Apple Mail) can open .822 files by simply importing them or opening them as saved messages.
  2. Text editors (like Notepad on Windows, TextEdit on macOS, or VS Code) can open .822 files to view the raw text content.
  3. Use online converters or dedicated email archiving tools to import or view these files.

What is a .822 file?

.822 files represent email messages in a standardized format defined by RFC 822. This format specifies the structure for headers, such as 'From', 'To', and 'Subject', as well as the message body. It was one of the foundational standards for electronic mail, enabling different email clients and systems to exchange messages reliably. While newer standards like RFC 5322 have superseded it, the .822 format is still recognized and understood by most modern email software.

Programs That Open .822 Files

PlatformProgram
WindowsMozilla ThunderbirdFree
Microsoft OutlookPaidOfficial
NotepadFreeOfficial
macOSApple MailFreeOfficial
Mozilla ThunderbirdFree
TextEditFreeOfficial
LinuxMozilla ThunderbirdFree
EvolutionFreeOfficial
GeditFreeOfficial
AndroidGmail AppFreeOfficial
K-9 MailFree
iOSApple MailFreeOfficial
Gmail AppFreeOfficial
Web BrowserGmailFreeOfficial
Outlook.comFreeOfficial

How to Convert .822 Files

FormatMethod
.EMLEmail client export, Online converters
.TXTText editor, Email client export

Common Problems with .822 Files

⚠️ Cannot open directly in web browser.
Open the file in a dedicated email client or text editor. For viewing in a browser, you might need to use an online viewer or convert it to a more browser-friendly format.
⚠️ May not display rich text or HTML formatting correctly.
RFC 822 is a plain text format. For emails with HTML or rich content, look for MIME-encoded files (often with .eml or .msg extensions) which are more robust.

Frequently Asked Questions

Is .822 the same as .eml?

While both represent email messages, .822 is the older, foundational standard. .eml files often use MIME extensions to support richer content like HTML and attachments, making them more common for modern email saving.

Can I send an .822 file as an email attachment?

Yes, an .822 file itself is essentially a plain text email message and can be attached to another email. However, it's more common to send emails through a mail client directly rather than attaching raw message files.

Does .822 support attachments?

The original RFC 822 standard does not directly support binary attachments. Modern email formats (often using MIME) are used to encode and attach files, and .eml files are more likely to contain these.

Technical Details

The RFC 822 format is a plain text file structure. It consists of a header section, which contains metadata about the email, followed by a blank line and then the body, which is the actual content of the message. The headers are key-value pairs, separated by a colon, defining fields like sender, recipient, subject, date, and content type.

Did You Know?

RFC 822 was published in 1982, hence its name.
It laid the groundwork for nearly all subsequent email communication standards.

Security Information

As plain text files, .822 files can be inspected for malicious content. Be cautious when opening emails from unknown sources, as the content or any embedded links could be harmful. Avoid executing any embedded scripts or opening unexpected attachments.

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