Filter text lines
Keep or remove lines containing a specific piece of text.
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We do not send your file or text contents to a processing server. No account is needed and there is no daily operation quota. Individual tools have size limits to protect your device’s memory.
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How we handle your data →How to use this tool
- Paste one entry per line.
- Enter a literal search and choose keep or exclude.
- Check the count, order and letter-case differences.
An example you can verify
Separate errors from a log without modifying matching lines.
Example input
ERROR: A INFO: B error: C
Expected result
ERROR: A error: C
2 of 3 lines remain. Exclude mode retains only INFO: B.
Keep only lines containing a word
Matching is literal and can also match part of a word. Keep or exclude matching lines, choose case sensitivity and check the count. Order and duplicates are preserved.
Settings and limits
Paste a list, enter the search text and choose whether to keep or exclude matches. Matching is literal: dots, brackets and other symbols are not regular expressions. You can enable case sensitivity. Order, duplicate lines and whitespace are preserved. Maximum 1 million text characters and 1,000 search characters.
Frequently asked questions
What happens to blank lines?
They cannot contain a nonempty search string. Keep mode excludes them; exclude mode retains them. A result with no matching lines can be empty.
Are my data stored on a server?
No. Content and files are processed in your browser without an account. Closing the page loses unsaved results.