CLF to CSV Converter - Common Log Format Parser

Convert Common Log Format (CLF) and Combined logs to CSV. Parse web server access logs from any platform. Browser-based tool.

Drop access log file here or click to browse

.log, access.log, .txt files

Log Input

Include Referer

Include User-Agent

CSV Output

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Frequently Asked Questions

CLF is the standard format for web server access logs, defined by the W3C. It includes IP, identity, user, timestamp, request, status code, and response size.

Combined Log Format extends CLF with two additional fields: referer (where the user came from) and user-agent (browser/client information).

Apache, Nginx, IIS, and most web servers can output CLF. It's the most portable log format across different server software.

IP address, RFC 1413 identity, authenticated user, timestamp, HTTP method, URL path, protocol version, status code, and response bytes.

Timestamps are preserved in their original format (e.g., 15/Oct/2023:10:30:00 +0000) for accurate time zone representation.

Yes. All parsing happens locally in your browser. Access logs containing visitor IPs and URLs never leave your device.

Browser memory limits apply. For files over 50MB, consider using command-line tools or splitting the file first.

Invalid lines are skipped and counted. The stats show both parsed and skipped line counts.

This tool handles standard CLF and Combined formats. Custom formats may require the Apache-specific log parser.

After converting to CSV, use spreadsheet software or database tools to filter by status code, IP, URL pattern, etc.

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