hl

hl [-l level] [-f filter] [--since time] [--until time] [-P] [-L] [file...]

hl is a high-performance log viewer and processor that converts JSON logs and logfmt logs into clear human-readable format. It automatically detects log formats and renders them with color-coded output for quick analysis.
The tool supports field-based filtering, log level filtering, and timestamp range filtering. It automatically integrates with a pager (defaulting to less) and supports theme customization through configuration files.

-l LEVEL

Filter by log level (debug, info, warn, error)

Filter by field value

Show logs after this timestamp

Show logs before this timestamp

Disable pager (streaming mode)

Show timestamps in local timezone

Show timestamps in specified timezone

Process logs with non-JSON prefixes

Designed for structured log formats (JSON, logfmt); plain text logs are passed through as-is. Very large log files benefit from the tool's streaming mode to avoid buffering the entire file in memory.

hl was created by pamburus and is written in Rust. It was designed as a blazing-fast alternative to tools like jq for log analysis, with built-in understanding of common log formats and levels.

jq(1), less(1), tailspin(1)