List Converter
ConverterSort, dedupe, reverse and transform lists with custom separators and case conversion for cleaning up pasted data and performing bulk text edits.
About List Converter
Copy a column from a spreadsheet to build a SQL IN clause, or split a comma-separated string into one item per line — shuffling lists between delimiters is fiddly busywork. This tool transforms lists locally in your browser: convert between newline, comma, and space delimiters, and bulk-add prefixes, suffixes, quotes, plus dedupe, sort, and drop empty lines. Everything runs on your machine, so pasted business data is never uploaded. Tip: Bookmark this tool for quick access whenever you need format conversion. All processing happens locally in your browser — no data upload, so feel free to paste sensitive content.
How to Use
- Open the List Converter tool page
- Enter or paste your data into the input area
- View the real-time results and use the copy button to get the output
Use Cases
- Build IN clause — Quote each ID and join with commas to paste straight into a SQL IN query.
- Clean pastes — Dedupe and drop blank lines from multi-row data copied out of a spreadsheet.
- Make arrays — Add quotes and commas per line to assemble a string array literal in code.
- Comma to lines — Split a comma-separated tag line into one per line to review each item.
- Add a prefix — Bulk-prepend a path prefix or append an extension to a batch of filenames.
- CSV to array — Convert a comma-separated list from a spreadsheet into a JS/JSON array format for code.
- Deduplication filter — Remove duplicate entries from a newline-separated list before importing into a database.
FAQ
Which delimiters are supported?
Newline, comma, semicolon, space, and tab all work as input or output delimiters, and you can set a custom separator for special formats.
Is dedupe case-sensitive?
By default it removes exact string duplicates, i.e. case-sensitive. Enable the relevant option to ignore case or trim surrounding whitespace.
Are empty lines kept?
Optional. With drop-empty enabled, whitespace-only lines are removed; otherwise they are preserved so you stay in control of the result.
Is sorting alphabetical or numeric?
Default is lexicographic, so 10 sorts before 2. For numeric order, make sure the data is purely numbers and pick numeric sort mode.
Does adding quotes handle existing quotes?
Bulk-quoting wraps each item in quotes. If an item already contains quotes, extra escaping may be needed — verify the resulting SQL or code afterward.
Any browser compatibility requirements?
This tool works in all modern browsers (Chrome, Firefox, Edge, Safari). No plugins or extensions required.
Can I use it offline?
After initial load, most features work offline. The core logic runs entirely in your browser with no network dependency.
Comments
Comments are stored locally in your browser. Configure Giscus for cloud-based comments.