Log Parser

What is Log Parser?

Log Parser interprets and formats log lines from common formats including JSON logs (structured logging), Apache Combined/Common format, Nginx access logs, syslog (RFC 3164/5424), and generic timestamp-prefixed lines. It extracts fields like timestamp, log level, source, message, and metadata into a searchable, sortable table with syntax highlighting and filtering by severity level.

SRE engineers investigating incidents, DevOps engineers analyzing server logs, and backend developers debugging request flows across services. The tool runs entirely in your browser — your data never leaves your device.

How to Use Log Parser

1. Paste your log output — JSON, Apache, Nginx, syslog, or generic format — into the input
2. The parser auto-detects the format and extracts fields into structured columns
3. Filter by log level (ERROR, WARN, INFO, DEBUG) to focus on relevant entries
4. Sort by timestamp, status code, or response time to identify patterns
5. Copy the parsed table or export it as CSV for further analysis

Common Use Cases

• Parsing JSON-formatted CloudWatch or Stackdriver logs into readable structured tables
• Analyzing Nginx access logs to identify slow requests, error codes, and traffic patterns
• Extracting error-level entries from syslog output during incident investigation
• Formatting Docker container logs that mix JSON and plain text output formats
• Parsing application logs to extract request IDs and trace correlation data for debugging

Pro Tips

• For JSON logs, look for correlation IDs and request IDs to trace individual requests across services during debugging
• Apache and Nginx log formats use different default field orders — check which log_format directive your server uses if the parser misaligns columns
• Filter for 5xx status codes first during incident investigation — they indicate server errors and are usually the most relevant entries for root cause analysis

Why Use This Tool?

• Privacy-first: All processing happens locally in your browser. No data is transmitted to any server.
• No installation required: Works in any modern browser on desktop or mobile.
• Completely free: No account, no credit card, no usage caps.
• Fast and reliable: Powered by modern Web APIs for near-instant results.

Related Concepts

Learn more about related topics: Structured logging, ELK stack, Log aggregation, Syslog RFC 5424.

Frequently Asked Questions