Manage large text files and logs more effectively with the Line Filter tool. This utility allows you to keep or discard lines of text based on specific keywords or complex regular expressions. Whether you're stripping comments from code, isolating errors from logs, or cleaning up a mailing list, this tool provides the precision you need to refine your data fast.
Privacy Protected
Free Online Line Filter Utility
Keep or remove lines from a text block based on keywords or regex patterns. Powerful text processing tool. Fast, free, and 100% private browser tool.
Share Tool
Select files or drag & drop here
Processed 100% locally in your browser. Your files never touch an external server.
Choose File to Begin
100% Client-Side Privacy•No File Size Limits•Free Forever
About Free Online Line Filter Utility
FusioFiles 100% Client-Side Privacy Guarantee
Your files and data never leave your browser — processed directly on your device.
Zero Server UploadsExecution occurs entirely in browser memory via WebAssembly and HTML5 Canvas.
HIPAA & GDPR ReadySafe for confidential tax forms, medical records, financial sheets, and legal contracts.
Zero Cloud LatencyInstant results with no upload delays, server queues, or third-party tracking.
Automatic RAM PurgeBuffers and caches are automatically wiped clean the instant you close the tab.
1
Paste Text
Input your text block into the main editor.
2
Set Rule
Select whether to 'Keep' or 'Remove' lines containing specific text.
3
Enter Keyword
Type the keyword or regex pattern to filter by.
4
Filter
The results update instantly as you change the rules.
Key Features
Conditional Rules
Choose to 'Include' only relevant lines or 'Exclude' unwanted data points.
Regex Support
Use powerful Regular Expressions for advanced pattern-based filtering.
Instant Refresh
Observe your filtered output update in real-time as you type your criteria.
Frequently Asked Questions
Yes, you can use regular expressions for advanced line filtering.
The tool typically performs case-insensitive filtering by default.
Related Tools
View allLast updated on