FIX Doctorsupport@fixdoctor.tech
FIX Knowledge Base

Free FIX Log Parser Online

FIX Doctor is a free, instant FIX log parser that analyzes your FIX protocol messages, detects errors, identifies sequence gaps, and provides detailed diagnostics. Upload your FIX log files or paste raw FIX text directly into the parser for immediate analysis.

How It Works

  1. Upload or Paste: Upload a FIX log file (.txt, .log, .fix) or paste raw FIX message text directly into the parser.
  2. Automatic Parsing: FIX Doctor automatically detects field delimiters (SOH, pipe, semicolon) and parses all FIX messages.
  3. Error Detection: The parser identifies missing mandatory tags, invalid values, sequence gaps, and other FIX protocol errors.
  4. Detailed Results: View a comprehensive diagnostic summary with error explanations, message timeline, and suggested fixes.

Features

  • Instant Analysis: Parse FIX logs in seconds, no installation required
  • Error Detection: Automatically detects missing tags, invalid values, sequence gaps, and reject codes
  • Message Timeline: Visual timeline of all FIX messages with timestamps and sequence numbers
  • Tag Expansion: See human-readable tag names alongside tag numbers
  • Share Results: Generate shareable links to diagnostic results
  • Export Reports: Download PDF reports of your analysis (Pro feature)

Supported File Types

FIX Doctor supports common FIX log file formats:

  • Plain text files (.txt, .log, .fix)
  • FIX messages with SOH delimiters (ASCII 0x01)
  • Pipe-delimited FIX messages (|)
  • Semicolon or comma-delimited formats
  • Raw FIX text pasted directly

Common Use Cases

  • Troubleshooting Rejects: Quickly identify why orders are being rejected by brokers
  • Sequence Gap Analysis: Detect missing messages and sequence number issues
  • Message Validation: Verify FIX messages are correctly formatted before sending
  • Onboarding Testing: Validate FIX connectivity during broker onboarding
  • Error Diagnosis: Understand FIX error codes and reject reasons

Start Parsing Your FIX Logs

Upload or paste your FIX logs now for instant analysis and error detection.

Parse FIX Logs Now

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