Free online line batch processing tool: add prefix/suffix, remove empty lines, line numbers, dedupe, reverse, filter — all in one click.
TL;DR: Free line batch processor supporting prefix/suffix, remove empty lines, line numbers, dedupe, reverse, filter and sort. Process text lines in one click, runs locally.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Usage Guide
Process hundreds of text lines at once: add a uniform prefix, strip line endings, filter by keyword, number every line — line-by-line editor work does not scale. This tool composes line-level batch operations as a checkbox pipeline: prefix/suffix, delete empty lines, line numbering, dedupe, reversal, filtering (include/exclude), sorting — stackable, executed locally.
1. How to use
- Paste the text to process, one record per line.
- Enable operations as needed: add prefix/suffix, remove empty lines, number lines, dedupe, reverse order, filter by keyword or regex (include/exclude), sort.
- Operations run in order and stack; preview on the right and copy when satisfied.
2. Common combinations
- Bulk SQL: prefix every line with "INSERT INTO t VALUES (" and suffix it with ");".
- Log cleanup: remove empty lines + filter by ERROR + reverse (newest first).
- Indexed exports: line numbering plus prefix keeps sequence numbers for row-level tracing.
- Dedupe + sort stacks into lightweight data cleaning — the last tidy-up before excel-to-json.
3. Operation order decides the result
Filtering before or after numbering changes semantics: filter-then-number yields a contiguous new sequence; number-then-filter keeps the original file line numbers (with gaps). Operations run in checkbox order, so place read-only steps first and numbering after you have confirmed the filter. Before generating bulk SQL, escape field values containing quotes or commas — route through a CSV tool or a dedicated escaper first.
FAQ
Nine stackable line-level operations: add prefix, add suffix, remove empty lines, trim whitespace, add line numbers, dedupe, reverse order, filter by keyword, and sort — tick them in the order you need and combine freely.
It does. Whether filtering runs before or after dedupe, whether line numbers count empty lines, and which language rules the sort follows all change the output. Try a small sample first and confirm it looks right before running the full text.
Yes. Enter a keyword and choose include or exclude mode to screen out the lines you need. After filtering, spot-check the first and last lines before copying the result.
Run a regression with a sample whose correct output you already know: fix the input and options, and the output should be predictable. Record the line count before and after a batch, and when handing results to others, attach the options used and the boundaries you do not guarantee.
No. The page is free to open, with no account required; every operation finishes inside your browser, with no usage cap.
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