String Builder

How to use it

1. Paste one item per line into the left panel.
2. Pick the delimiter: comma, newline, semicolon or a custom string such as | or ::.
3. Add a prefix and suffix if every item needs the same wrapper, for example ( and ).
4. Choose quote wrapping — none, single or double — and switch on escaping when the values themselves contain backslashes or quotes.
5. Read the joined string on the right; it rebuilds as you type. Trim and skip-empty are on by default and can be turned off.

Common use cases

• SQL IN lists — join quoted ids into ('a', 'b', 'c') with a comma delimiter and single quotes.
• Code array literals — build ["a", "b"] style lines with a comma delimiter, double quotes and a newline suffix.
• Path or URL lists — assemble pipe-separated or comma-separated lists for config files and CLI flags.
• Repeated wrappers — add the same prefix and suffix to every line, for example wrapping log tokens or CSS class names.

Why it stays private

Everything runs in your browser's memory. Lists of ids, emails or tokens are exactly the kind of content that should not be sent to a server, and nothing is uploaded.

FAQ

Q: What does the escape switch do? A: When quotes are enabled and escaping is on, backslashes and the chosen quote character inside each value are prefixed with a backslash, so O'Hara becomes 'O\'Hara' instead of breaking the string.

Q: Can I keep blank lines or indentation? A: Yes. Turn off Skip empty lines to keep blank entries, and turn off Trim whitespace to preserve the spaces at the start and end of each line.

Q: Does the delimiter get inserted between every pair of items? A: Exactly one delimiter goes between consecutive items — none before the first and none after the last, which is the shape most languages and config formats expect.