Bulk Replace – Multi-file find & replace (text)
About this tool
Apply bulk find-and-replace rules to multiple text-based files (.txt, .md, .csv, .tsv,
.html, .css, .js, and more). All processing happens entirely in your browser (no data is sent).
Replacement rules
| Search (pattern) | Replace (replacement) | Regex | Case | Word boundary | Delete |
|---|
Apply mode:
Add files
Drag & drop files here, or
0 files.
Run & results
| File name | Type | Original size | Replacements | Download |
|---|
Files are read as UTF-8 (a BOM is not added). Confirm the output encoding and newline style as needed.
How to use
- Drag and drop your files into “Add files” (or click “Choose files”).
- Paste CSV/TSV rules (column 1 = search term, column 2 = replacement) into “Replacement rules” and press “Expand into table.” You can also add rows manually.
- Select Sequential replace / Simultaneous replace as needed, and toggle Regex / Case / Word boundary for each row.
- Click “Run replace,” then download files individually or as a ZIP bundle. Exporting the log CSV is also available.
Notes
- Sequential replace: applies rules from top to bottom. Results may match later rules again (chaining).
- Simultaneous replace: determines all match ranges first, then replaces them together—useful to avoid chains such as a → b and b → d.
- Regex: interpret the search text as a regular expression (example
(\d{2,3})-(\d{4}) → $1$2). - Case: enable to match case-sensitively. When off it behaves like the
iflag (Color / color / COLOR are treated the same). - Word boundary: wraps the pattern with
\bto limit matches to alphanumeric words (less effective for Japanese text).