1st

.1stFirst Choice Text Document

Various (text-based files) · 1980s

Developer
Various (text-based files)
Category
Documents
MIME Type
text/plain
First Released
1980s
Open Format
Yes
File Signature
N/A (Plain text files typically do not have a specific header signature)
At a Glance
.1st
First Choice Text Document

A .1st file is a simple, unformatted plain text document, often used for basic notes or configuration data.

Reviewed on May 4, 2026
Compression
Plain text
Transparency
No
Editability
High
Best for
Plain text storage

Key Features

  • Universal Compatibility: Opens on nearly any operating system or device.
  • Simplicity: Contains only raw text characters, no formatting or embedded objects.
  • Small File Size: Due to the lack of rich data, files are typically very compact.
  • Human-Readable: Easily viewed and edited with any basic text editor.

Best For

  • Cross-platform text sharing.
  • Storing plain, unformatted data.
  • Quick, simple notes.
  • Configuration files.

Less Ideal For

  • Documents requiring rich formatting (bold, italics, fonts).
  • Presentations with slides and graphics.
  • Spreadsheets with calculations and charts.
  • Image, audio, or video files.

Common Use Cases

  • Storing simple text notes or memos.
  • Saving configuration settings for software.
  • Distributing basic readme files.
  • Creating simple lists or outlines.

How to Open It

  1. On Windows: Double-click the file to open in Notepad, or right-click and choose 'Open with...' to select another text editor like Notepad++.
  2. On macOS: Double-click to open in TextEdit, or use a terminal command like 'open file.1st'.
  3. On Linux: Open with any text editor such as Gedit, Nano, Vim, or Emacs.
  4. Mobile Devices: Use a dedicated text editor app available on app stores.

What is a .1st file?

The .1st file extension is generally used for plain text files. These files are designed to be universally compatible, meaning they can be opened and read by virtually any text editor or word processor. Unlike more complex document formats, .1st files contain only basic character data, without any special formatting, images, or embedded objects. This simplicity makes them ideal for storing raw text information, configuration settings, or simple notes that need to be accessed across different operating systems and applications. Because they are unformatted, they are also very small in size.

Programs That Open .1st Files

PlatformProgram
WindowsNotepadFreeOfficial
Notepad++Free
macOSTextEditFreeOfficial
LinuxGeditFreeOfficial
NanoFreeOfficial
VimFreeOfficial
AndroidQuickEdit Text EditorFree
iOSTextasticPaid
Web BrowserGoogle DocsFree

How to Convert .1st Files

FormatMethod
.TXTSave As/Export in text editor, Command-line tools (e.g., `cp file.1st file.txt`)
.RTFCopy-paste into a word processor and save as RTF, Some advanced text editors might support export.

Common Problems with .1st Files

⚠️ File won't open or displays gibberish.
This usually means the file is not plain text or is corrupted. Ensure it's a .1st file and try opening it with a robust text editor. If it contains non-textual data, it's not a true .1st file.
⚠️ Formatting is lost when opening.
This is expected. .1st files are plain text and do not store formatting. If formatting is important, use a document format like .docx or .rtf instead.

Frequently Asked Questions

What is the main purpose of a .1st file?

Its primary purpose is to store simple, unformatted text data that needs to be universally compatible and easily readable.

Can I put images or tables in a .1st file?

No, .1st files are strictly for plain text. They cannot contain images, tables, or any rich formatting elements.

Is a .1st file the same as a .txt file?

Essentially, yes. Both are plain text formats, and the .1st extension is often used interchangeably with .txt, sometimes to denote a primary or 'first' file in a set.

Technical Details

These files are essentially ASCII or UTF-8 encoded text. They do not contain any formatting codes, images, or other rich media, adhering strictly to plain text standards. File structure is a linear sequence of characters, typically terminated by newline characters. A common characteristic is the absence of a specific header signature, relying solely on the file extension for identification.

Did You Know?

The '.1st' extension is often a convention rather than a strictly defined standard, implying it's the 'first' or primary text file in a collection.
Because they are plain text, .1st files are generally safe from malicious code execution, unlike executable files.

Security Information

As .1st files are plain text, they do not contain executable code and are generally considered safe. However, always be cautious when opening files from unknown sources, as they could potentially contain links or information that leads to security risks.

Related Extensions