Log Viewer
View, search, and analyze log files directly in your browser. Upload or paste lo...View, search, and analyze log files directly in your browser. Upload or paste log data to filter by level, search with regex, bookmark important lines...
Drop a log file here or click to browse
Supports .log, .txt, .out, .err files
Ctrl+Enter to load
Log Viewer Features
Analyze logs without installing anything
Why Use Log Viewer?
Level-Based Filtering
Instantly filter by ERROR, WARN, INFO, or DEBUG levels. Each level is color-coded with count badges so you can focus on what matters.
Regex Search & Highlight
Search with plain text or regular expressions. Matching lines are highlighted and counted. Filter to show only matching lines.
Virtual Scrolling
Handle log files with 100K+ lines smoothly. Only visible lines are rendered, keeping the viewer fast even with massive files.
Bookmarks & Navigation
Bookmark important lines by clicking line numbers. Jump between bookmarks to quickly navigate back to key events.
Common Use Cases
Why view logs online
Debug Application Errors
Filter to ERROR and WARN levels to quickly find exceptions and stack traces. Search for specific error codes or messages.
Monitor Server Logs
Load server access or application logs to check request patterns, response times, and error rates at a glance.
Security Audit
Search for suspicious patterns like failed login attempts, unauthorized access, or unusual IP addresses in security logs.
Performance Analysis
Analyze log timestamps to identify slow operations, bottlenecks, and timing patterns across your application stack.
How It Works
Load Log Data
Drag and drop a log file, paste log text directly, or load the sample data to explore features.
Filter by Level
Toggle ERROR, WARN, INFO, and DEBUG buttons to show or hide lines by severity. Each button shows a count badge.
Search & Analyze
Use the search bar with regex support to find specific patterns. View stats like line counts per level and time range.
Export Results
Download filtered lines as a text file or copy visible lines to clipboard. Share findings with your team.
Pro Tips for Log Analysis
Start with Errors
Toggle off INFO and DEBUG first to see only errors and warnings. This gives you the fastest path to finding problems.
Use Regex Patterns
Search for patterns like 'timeout|connection refused' to find multiple error types at once. Regex makes complex searches easy.
Bookmark Key Lines
Click line numbers to bookmark important entries. Then use the bookmark navigation to jump between them when correlating events.
Use Dark Mode
Dark mode (the default) reduces eye strain during long debugging sessions. The color-coded levels stand out better on dark backgrounds.
Frequently Asked Questions
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