How to open a code or text file online
Three steps, a few seconds, no software.
Open your .LST file
Drop it on the box, choose it from your device, or paste the text straight in.
View it instantly
Your .LST file opens neatly formatted with line numbers.
Search, copy or download
Search the text, jump to any line, then copy what you need or download a clean copy.
What is a .LST file?
Plain text that programs, servers and people write every day.
A .lst file is a plain-text list: file names, paths, values, or a compiler/assembler listing, usually one entry per line. Open it in any text editor: Notepad++ or Notepad on Windows, TextEdit on Mac, gedit or nano on Linux. If the contents look like random characters, the program that created it used a binary format and you need that same program to open it.
Programs that open .LST files
| Full name | List File (generic plain-text list / listing) |
|---|---|
| Developer | N/A — generic extension reused by many programs |
| First released | No single origin — a long-standing convention across DOS/Unix tools and many applications |
| Category | Text & Code |
| MIME type | text/plain |
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Frequently asked questions
Is my .LST file uploaded anywhere?
No. The file is read and highlighted for you.
Why do some characters look wrong (é, ł)?
That usually means the file was saved in one encoding and opened in another. We detect UTF-8, UTF-16 and the Windows-1250/1252 code pages automatically and show which one was used.
Can it handle huge log files?
Yes, up to 50 MB. Only the lines on screen are drawn, so scrolling stays smooth. Syntax colours are switched off for files over 1.5 MB to keep things fast.
How do the log level filters work?
We find levels like ERROR, WARN, INFO and DEBUG on each line. Lines without a level, such as stack traces, stay with the entry above them, so filtering to errors keeps the full trace.
Can I edit the file?
This is a viewer. To change code, download it or copy it into your editor. Converting encodings and line endings is planned.
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