head to head · open source
monolog vs logging-log4j2
monolog has 21,405 GitHub stars, 1,910 forks, 3 open issues and last shipped yesterday. logging-log4j2 has 3,636 stars, 1,744 forks, 212 open issues and last shipped yesterday. monolog leads on adoption by 489% (21,405 vs 3,636 stars). monolog is written in PHP under MIT; logging-log4j2 is written in Java under Apache-2.0. monolog has attracted 9% as many forks as stars, logging-log4j2 48%. monolog was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 2 topic tags (logger, logging), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| monolog | logging-log4j2 | |
|---|---|---|
| GitHub stars | ★ 21K | ★ 3.6K |
| License | MIT | Apache-2.0 |
| Written in | PHP | Java |
| Last push | 2026-09-19 | 2026-09-19 |
| Forks | ⑂ 1.9K | ⑂ 1.7K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick monolog if
- You weight community size — 21K stars and counting
- You want the MIT license terms
- Your stack matches PHP
- You value the larger contributor base for long-term maintenance
pick logging-log4j2 if
- You want the logging-log4j2 feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Java
- You evaluated both and logging-log4j2 fits your workflow better
About monolog
Monolog is a logging library for PHP that sends log records to files, sockets, inboxes, databases, and various web services. It ships with the handlers, formatters, and processors needed to route records where they belong, and special handlers allow more advanced logging strategies than a single output stream. The library lives in the PHP ecosystem and is distributed through Packagist as monolog/monolog . It is released under the MIT license and has been developed for sixteen years, with more than twenty one thousand stars and roughly nineteen hundred forks on GitHub.
read the full monolog overview →
About logging-log4j2
Apache Log4j 2 is a versatile, industrial grade Java logging framework, composed of a logging API, its implementation, and components that assist deployment for various use cases, built for Java and JVM developers who need a logging stack inside their applications.
read the full logging-log4j2 overview →
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Frequently asked questions
Is monolog or logging-log4j2 more popular?
monolog has 21,405 GitHub stars and logging-log4j2 has 3,636. monolog has the larger community by that measure.
Are monolog and logging-log4j2 free?
Both are open source. monolog is licensed under MIT and logging-log4j2 under Apache-2.0. Neither carries a licence fee.
What is the difference between monolog and logging-log4j2?
monolog is written in PHP and logging-log4j2 in Java. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, monolog or logging-log4j2?
Choose monolog if you want the larger community (21,405 stars) or its MIT licence terms. Choose logging-log4j2 if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.