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Grep - Filter lines by pattern

How does it work?

This tool filters lines in text based on a search pattern, similar to the Unix grep command. It keeps only the lines that match the specified pattern and discards the rest.

The filtering options include:

Case sensitivity: When enabled, matches must have the exact same case as the pattern
Regular expressions: When enabled, the pattern is treated as a regular expression for more powerful matching

Example

Original text:

The quick brown fox jumps over the lazy dog.
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
This line contains FOX in uppercase.
Another line with the word "fox" in lowercase.
1234 - This line has numbers.
Regular expressions are powerful.
The pattern /^T/ matches lines starting with T.
The end.

Example 1: Filter lines containing "fox" (case insensitive)

The quick brown fox jumps over the lazy dog.
This line contains FOX in uppercase.
Another line with the word "fox" in lowercase.

Example 2: Filter lines containing "T" at the beginning (using regex ^T)

The quick brown fox jumps over the lazy dog.
This line contains FOX in uppercase.
The pattern /^T/ matches lines starting with T.

Regular Expression Tips

When "Use regular expressions" is enabled, you can use patterns like:

^ - Match the beginning of a line (e.g., ^The matches lines starting with "The")
$ - Match the end of a line (e.g., end\.$ matches lines ending with "end.")
\d - Match any digit (e.g., \d+ matches one or more digits)
\w - Match any word character (letters, numbers, underscore)
.* - Match any characters (e.g., a.*z matches lines with "a" followed by any characters and then "z")

This tool is useful for:

Extracting specific information from logs or data files
Finding all lines containing a particular keyword
Filtering text based on complex patterns using regular expressions
Reducing large text files to only the relevant lines
Analyzing data by isolating lines that match specific criteria

Related Tools

Inverted Grep - Find lines that don't match a pattern
Group by Grep - Group lines by matching patterns
Select Occurrences - Find and select all occurrences of a pattern
Format to Columns - Format delimited text into aligned columns
Count Words - Count words, characters, and lines in text

All Tools

See all available tools

Text tools

Decode base64 text Base64 encode text Trim whitespaces Decode URL text URL encode text Change text to uppercase Change text to lowercase Count words, lines, paragraphs

Encode/Decode

Encode text to MD5 Hex Encode text to SHA-1 Hex Encode text to SHA-256 Hex Encode text to SHA-512 Hex Encode text to SHA3-256 Hex Encode text to SHA3-512 Hex Encode text as URL Decode URL text Encode text to Base64 Decode Base64 text Encode text to Hex Decode Hex text ISO Timestamp to Epoch Milliseconds Epoch Milliseconds to ISO Timestamp

Increment/Decrement

Increment all numbers Decrement all numbers Duplicate and increment numbers Duplicate and decrement numbers Create sequence Increment duplicate numbers

Sort

Reverse order of lines Shuffle lines Sort case-sensitive A-z Sort case-sensitive z-A Sort case-insensitive A-Z Sort case-insensitive Z-A Sort line length ascending Sort line length descending Sort hexadecimally Sort lines by subselection Sort tokens Shuffle Characters JSON sort Hierarchical sort

Align

Align carets/selections Format text to columns/table Align text to left Align text to center Align text to right

Filter/Remove/Trim

Grep Inverted Grep Group by Grep Trim Trim Leading Trim Trailing Replace whitespaces with space Remove all spaces Remove duplicates Keep only duplicate lines Group and Count Remove empty lines Remove consecutive empty lines Remove all newlines

Convert/Minify

Convert Between Char and Int Minify JSON Minify JavaScript Convert Between JSON and YAML

Other

Reverse Letters Swap Words Swap Characters/Selections/Lines/Tokens Wrap or shift quotes Swap between quotes Straighten/Educate quotes Switch file path separators Select All Occurrences For All Carets Extend Selection in Different Mode Multi Replace Duplicate and Multi Replace Paste - camelCased Paste - and Keep Selections Create Border