Structured application logs
JSON Log Analyzer
Analyze newline-delimited JSON records and automatically detect common timestamp, level, message, request, response, client, and service fields.
Drop a log file here
.log, .txt, .json, .jsonl, .ndjson, or .clef · format is detected from content
Paste logs instead
Structured field detection
The analyzer matches common logging names for timestamps, levels, messages, HTTP status, method, path, response time, IP, service, environment, bytes, user agent, and exception class. Unknown properties remain visible in the raw JSON line.
Malformed NDJSON
Each JSON line is parsed independently. An invalid object is counted as skipped and does not invalidate the rest of the file.
Private, local log analysis
Files are sliced and processed by a Web Worker in your browser. ToolsWeave does not upload log content, filenames, IP addresses, URLs, messages, or stack traces. Exports are also generated locally.
JSON Log Analyzer FAQ
Does it support a JSON array?
The streaming parser is designed for one JSON object per line (NDJSON/JSONL), not one large top-level array.
What if my field names are custom?
Common aliases are detected automatically. Manual custom-field mapping is not yet available.
Are log files uploaded?
No. Analysis runs in a browser Web Worker and the selected file is read in local chunks.
Can I analyze a large log file?
Yes. File input is chunked and aggregate counters are built incrementally. Full-file searches return 100 records per page and rescan the source when filters or pages change. Actual limits depend on the browser, individual entry size, and device.
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