String Join
Join multiple text lines into one with a custom separator. Free online tool, runs in your browser.
What is string joining?
String joining is the process of combining multiple lines of text into a single line by inserting a separator between each line. It is commonly used in programming, data formatting, and preparing CSV or SQL content.
How does this string join tool work?
Paste your multi-line text into the input area, choose or type a separator (such as comma, space, or any custom string), and the tool instantly merges all lines into one continuous string.
What separators are supported?
You can use any character or string as a separator: comma, space, semicolon, pipe, tab, newline (\n), or even multi-character strings like ' | ' or ' - '.
Can I join lines without any separator?
Yes. Leave the separator field empty and the tool will concatenate all lines directly, creating one continuous string with nothing between the original lines.
Is my data safe?
Absolutely. All processing happens locally in your browser. No text is uploaded to any server, and no data is stored or logged. Your content stays completely private.
Is there a limit on the number of lines?
There is no hard limit. Since the tool runs entirely in your browser using JavaScript, it can handle thousands of lines efficiently. Performance depends on your device.
What is the difference between string join and string split?
String join merges multiple lines into one string with a separator, while string split does the opposite — it breaks a single string into multiple parts based on a delimiter. They are inverse operations.
Can I use this tool for CSV formatting?
Yes. Paste one value per line, use a comma as the separator, and you will get a properly formatted CSV row ready to use in spreadsheets or databases.
Does the tool preserve line order?
Yes. The tool maintains the exact order of your input lines. The first line in the input becomes the first segment in the output, and so on.
Is this tool free?
Yes, it is completely free. No registration, no ads, no usage limits. You can use it as many times as you need.
How to Use String Join
Merge many lines of text into a single line with any separator you like, entirely in your browser. Your text is processed locally and never uploaded.
- Paste or type your list into the input box that says Enter text lines here...
- Set the Join with: field to your separator, such as a comma, semicolon, space, or arrow.
- Tick Delete blank lines to skip empty rows so no stray separators end up between items.
- Tick Trim trailing spaces to strip whitespace from the end of each line before joining.
- Copy the merged result that appears where the Result will appear here... placeholder was.
Use a comma plus space as the separator to turn a column of names into a ready-to-paste list for emails.
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