Log File Analyzer

Analyze web server logs for traffic patterns, security threats, and performance insights. Supports Apache, Nginx, and IIS log formats with compressed file handling.

Upload Log File

Supported formats: .log, .txt, .gz, .zip (max 50MB)
Optional processing limit
Only analyze entries after this date
Only analyze entries before this date
Filter by specific IP or CIDR range
Comma-separated status codes

About Log File Analysis

What does this tool do?

The Log File Analyzer processes web server log files to extract valuable insights about website traffic, visitor behavior, security threats, and performance metrics. It supports multiple log formats including Apache, Nginx, and IIS, with automatic format detection.

Why is log analysis important?

  • Security Monitoring - Detect attacks, brute force attempts, and suspicious activities
  • Performance Optimization - Identify slow pages and resource bottlenecks
  • Traffic Analysis - Understand visitor patterns and peak usage times
  • Content Strategy - See which pages are most popular and engaging
  • Technical Debugging - Find error patterns and troubleshoot issues

Who uses this tool?

  • Web Developers - Debugging applications and optimizing performance
  • System Administrators - Monitoring server health and security
  • Security Analysts - Investigating incidents and threat hunting
  • Digital Marketers - Understanding user behavior and traffic sources
  • Business Owners - Making data-driven decisions about web presence

How to use this tool

  1. Upload your log file - Select a web server log file (supports .log, .txt, .gz, .zip formats)
  2. Choose analysis options - Select log format (or use auto-detection) and set processing limits if needed
  3. Configure security settings - Enable IP reputation checking and real-time alerts for enhanced security analysis
  4. Start analysis - Click "Analyze Log File" to begin processing
  5. Review results - Explore different tabs for traffic, security, performance, and visitor insights
  6. Export data - Download analysis results in JSON, CSV, XML, or PDF format for further processing

Supported Log Formats

Apache Common Log Format
127.0.0.1 - - [01/Jan/2024:00:00:00 +0000] "GET / HTTP/1.1" 200 1234

Fields: IP, user ID, authenticated user, timestamp, request, status, size

Apache Combined Log Format
127.0.0.1 - - [01/Jan/2024:00:00:00 +0000] "GET / HTTP/1.1" 200 1234 "-" "Mozilla/5.0"

Includes referer and user agent information

Nginx Combined Log Format
$remote_addr - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent"
IIS W3C Extended Log Format
#Fields: date time s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status

Security Pattern Detection

This tool automatically identifies common security threats and attack patterns:

Brute Force Attacks
  • Multiple 401/403 status codes from same IP
  • Repeated login attempts
  • Password spraying patterns
Web Scanning
  • Accessing multiple sensitive endpoints
  • Directory traversal attempts
  • Vulnerability scanning tools
SQL Injection Attempts
  • Common SQL injection patterns in URLs
  • Union-based injection attempts
  • Error-based injection techniques
XSS and Code Injection
  • Script tag injections
  • JavaScript payload patterns
  • File inclusion attempts

Understanding Metrics and Results

  • Unique Visitors: Count of distinct IP addresses - indicates reach
  • Page Views: Total requests for pages - shows overall activity
  • Bandwidth: Total data transferred - impacts hosting costs
  • Peak Times: Hours with highest traffic - for scaling decisions
  • Threat Level High: Immediate attention required, likely active attack
  • Threat Level Medium: Suspicious activity, monitor closely
  • Threat Level Low: Minor anomalies, normal security noise
  • IP Reputation Score: 0-100 scale, higher = more dangerous
  • Error Rate: % of 4xx/5xx responses - indicates problems
  • Popular Pages: Most requested content - optimization targets
  • Resource Usage: File types and sizes - caching opportunities
  • Bot Traffic: Automated requests - may impact performance

Recommended Actions Based on Analysis

Security Recommendations
  • Block IPs with high threat scores at firewall level
  • Implement rate limiting for brute force protection
  • Review and patch vulnerabilities being scanned
  • Set up monitoring alerts for suspicious patterns
  • Consider implementing CAPTCHA for repeated failures
Performance Recommendations
  • Cache popular pages to reduce server load
  • Optimize images and large files based on usage
  • Scale resources during identified peak hours
  • Investigate and fix pages with high error rates
  • Consider CDN for frequently accessed content
User Experience Recommendations
  • Improve navigation to reduce 404 errors
  • Optimize mobile experience based on device data
  • Review referer data to understand traffic sources
  • Analyze user paths to improve site structure
  • Monitor bot traffic that may skew analytics

Technical Notes

File Processing
  • Maximum file size: 50MB
  • Streaming parser for large files
  • Automatic compression detection
  • Progress indicators for long operations
Privacy & Security
  • Files processed locally, not stored
  • IP addresses anonymized in exports
  • Temporary files cleaned automatically
  • Optional IP reputation checking