What joining lines does
Joining lines combines multiple lines of text into a single line, placing a separator of your choice between each piece. The classic use is turning a vertical list into a comma-separated string — three lines of "apple", "banana", "cherry" become "apple, banana, cherry". You choose what goes between the items, and the tool merges them. It is the counterpart to splitting text, and essential for packing a list into a single value.
Common joining tasks
The need comes up whenever a system wants a single delimited value instead of a list. You have a column of items and need them as a comma-separated string for a query or a spreadsheet cell. You want to turn a list of tags into a single tag string. You need to combine lines into one for pasting into a field that expects a single line. You are building a comma-separated list of IDs or emails from a vertical list. Joining does this instantly, no matter how many lines.
Choosing your separator
The separator is what goes between each joined item. A comma followed by a space is the most common, producing a readable comma-separated list. But you can use just a comma, a semicolon, a space, a pipe, a tab, or any custom string. This lets you produce exactly the format the destination expects. There is also an option to skip empty lines, so blank lines in your input do not produce empty gaps in the joined result.
Joining and splitting together
Joining and splitting are complementary. Join packs a list into a delimited string; split breaks a delimited string back into a list. Together they let you move data between a list format and a single-line format freely — split a comma-separated string into a list, edit or sort the list, then join it back. Both operations run in your browser, so your data never leaves your device.
Privacy: your text never leaves the browser
All processing happens locally, on your own device. Your text is never sent to servers, which makes the tool safe even for confidential content. When you close the tab, nothing remains stored.