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Developer Tools★ Free forever✓ No account🔒 No upload📴 Works offlineUpdated April 28, 2026
Free Pretty Log Formatter Online — No Signup Required
Pretty Log Formatter helps you Clean up JSON logs, key-value lines, and stack traces for readability — debug server logs instantly — free, in 2026, without leaving the browser. It is built for developers, QA engineers, and technical writers, so you can format, validate, transform, or inspect structured technical data with a fast public URL, clear output, and a workflow that stays focused on the task instead of setup.
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What is Pretty Log Formatter?
Log files from modern applications are often dense, machine-readable streams that are hard to scan visually. Structured JSON logs from Node.js (pino, winston), Python (structlog), and cloud platforms (AWS CloudWatch, GCP Cloud Logging) pack multiple fields onto a single line. Web server logs (Nginx combined format, Apache common format) use space-delimited fields with timestamps and status codes. A log formatter parses these formats and re-displays them with indentation, color-coding by severity, and aligned columns — turning an unreadable wall of text into a scannable incident review.
This tool identifies the log format automatically and applies the appropriate formatting. JSON logs are pretty-printed with severity color-coding (ERROR in red, WARN in yellow, INFO in gray). Nginx and Apache access logs are parsed into columns with the status code highlighted — 2xx in green, 3xx in blue, 4xx in orange, 5xx in red. The formatted output makes it much faster to identify error patterns, unusual status codes, and timing outliers during debugging sessions.
How to use Pretty Log Formatter in 3 steps
- 1
Paste your log output
Copy log lines from your terminal, server, or cloud console and paste them here. Mix of formats is supported.
- 2
Select format if needed
The tool detects JSON, Nginx, and Apache formats automatically. Select manually if auto-detection picks the wrong format.
- 3
Scan the formatted output
Error lines are highlighted in red. Scan for patterns, copy specific lines, or export the formatted version for incident reports.
Key features and benefits
- Auto-detects JSON, Nginx, and Apache log formats
- Color-codes severity levels and HTTP status codes
- Pretty-prints JSON logs with indentation
- No upload — paste and format in the browser
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References and standards
Pretty Log Formatter FAQs
Quick answers about the workflow, privacy, and where this tool fits in a broader job.
Does it support my log format?
The formatter handles JSON (any structured JSON log), Nginx combined/common access log format, and Apache common/combined log format. Custom log formats with regex-parseable patterns may be partially supported via the manual format selector.
Can I filter logs by level or status code?
Use the filter input to show only lines matching a severity (ERROR, WARN) or status code (5xx). This is a text filter, not a query language — for complex log queries, tools like Grafana Loki or ELK Stack are more appropriate.
Is my log data safe to paste here?
Log formatting runs in your browser — no log data is sent to any server. For logs containing personally identifiable information (user IDs, email addresses, IP addresses), be aware that the clipboard history on your device may retain the content after pasting.
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