Convert text file line endings
Switch a plain-text file between Windows (CRLF), Unix (LF), and classic Mac (CR) line endings.
Processed in your browser. This file is converted on your device and is never uploaded.
Converter
.txt up to 25 MB. You can also drag a file here.
No file selected.
About this tool
Text files mark the end of a line differently depending on the system that wrote them. Windows tools normally write a carriage return followed by a line feed (CRLF), Unix and macOS tools write a single line feed (LF), and very old Mac software wrote a single carriage return (CR).
Mixing these conventions causes files to appear as one long line in some editors, produces noisy diffs in version control, and can break scripts that expect a specific ending. This tool rewrites every line break in a text file to the convention you choose.
Supported formats and limits
- Input
- .txt
- Output
- .txt (text/plain)
- Output name
- The original name with the chosen line ending appended, for example notes.txt becomes notes-lf.txt.
- File size limit
- 25 MB
- Processing
- In your browser. The file is not uploaded.
How to use it
- Choose a .txt file, or drag one onto the file area.
- Select the line ending you want: Unix (LF), Windows (CRLF), or classic Mac (CR).
- Select Convert.
- Download the converted file. The original file on your device is not changed.
Limitations
- Only plain-text files are supported. A file containing binary data is rejected rather than corrupted.
- The file is read as UTF-8. Text saved in a different encoding, such as UTF-16 or a legacy code page, may not convert correctly.
- A byte order mark at the start of the file is preserved as-is.
- Line endings inside quoted strings or code are rewritten too, because the tool works on the whole file rather than parsing its contents.
- One file is converted at a time.
Common problems
The file was refused before anything started.
Convert text file line endings checks the extension before it reads a byte, and it accepts .txt. Browsers report file types inconsistently enough that the extension is what decides.
Rename the file if the extension is simply wrong, or convert it to one of those first. A file whose extension does not match its contents is refused for the same reason, and that one needs converting rather than renaming.
It said the file was too large.
The limit here is 25 MB. It is not a policy but a measurement: everything runs on your own device, and past that size a phone runs out of memory rather than finishing slowly.
Split the file, reduce it before converting, or use a desktop program for that one. A machine with more memory will manage more, but the limit does not know which machine it is on.
I selected several files and only one converted.
This tool takes one file at a time. Doing several at once would multiply the memory in use, which is the thing most likely to fail on a phone.
Convert them one after another. Nothing is kept between them, so there is no state to reset.
The tab reloaded itself part-way through.
The browser ran out of memory and restarted the page. At sizes approaching 25 MB this is the failure a phone hits first, and it looks like a crash rather than an error.
Try a smaller file, close other tabs, or run it on a computer. Nothing was uploaded or lost — the original file is untouched on your device.
The result opened in the wrong program.
The output is a .txt file, and your system opens that extension with whatever it was told to. Nothing about the conversion decides it.
Open it from inside the program you want, or change the default for .txt in your system settings. The file itself is correct.
Frequently asked questions
- Is my file uploaded anywhere?
- No. The conversion runs entirely in your browser using standard web APIs. The file never leaves your device, and no request carrying its contents is made.
- Which line ending should I choose?
- Use LF for Unix, Linux, macOS, and most version-control workflows. Use CRLF for Windows tools that require it, such as some Windows editors and older batch scripts. CR is only needed for software written for Mac OS 9 and earlier.
- What happens to a file that already mixes line endings?
- Every break is normalized to your chosen ending, so a file with a mix of CRLF and LF becomes consistent.
- Does the file size change?
- Yes, slightly. Converting from LF to CRLF adds one byte per line, and converting from CRLF to LF removes one byte per line.
- Can I convert several files at once?
- Not with this tool. Convert one file, reset, and then choose the next one.
- Do I need to install anything or create an account to use Convert text file line endings?
- No, to all of it. Convert text file line endings runs inside the browser you already have, with no sign-up, no download, no watermark on the result, and no cap on how many files you convert. There is nothing to uninstall afterwards either, because nothing was installed.
- Does Convert text file line endings work offline?
- Once the page has loaded, yes. The conversion runs on your device, so it needs no connection to do the work. The first visit fetches the page and the code that does the converting; after that a lost connection stops nothing, and a converted file appears exactly as it would online.
- How large a file can Convert text file line endings handle?
- The limit is 25 MB. It is a deliberate one rather than a technical ceiling: the real constraint is memory, and a file that decodes to more than the device can hold fails in a way that is hard to explain. Phones run out well before laptops do, which is why the limit is set where it is.
- Can I convert several files at once with Convert text file line endings?
- Not here: this tool takes one file at a time, because what it does depends on choices you make about that particular file. Convert them one after another, or look at the batch converters in the same category, which are built for a folder at a time.