head to head · open source
monolog vs Logstash
monolog has 21,401 GitHub stars, 1,920 forks, 3 open issues and last shipped 4 days ago. Logstash has 14,971 stars, 3,501 forks, 2,254 open issues and last shipped yesterday. monolog leads on adoption by 43% (21,401 vs 14,971 stars). monolog is written in PHP under MIT; Logstash is written in Java under a custom or non-standard licence. monolog has attracted 9% as many forks as stars, Logstash 23%. Logstash was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (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 | Logstash | |
|---|---|---|
| GitHub stars | ★ 21K | ★ 15K |
| License | MIT | Custom / other |
| Written in | PHP | Java |
| Last push | 2026-11-01 | 2026-11-04 |
| Forks | ⑂ 1.9K | ⑂ 3.5K |
| 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 Logstash if
- You want the Logstash feature set and don't need the biggest community
- You prefer the Custom / other license terms
- Your stack matches Java
- You evaluated both and Logstash fits your workflow better
About monolog
Monolog Logging for PHP Note This is the documentation for Monolog 3.x , if you are using older releases see the documentation for Monolog 2.x or Monolog 1.x Monolog sends your logs to files, sockets, inboxes, databases and various web services. See the complete list of handlers below. Special handlers allow you to build advanced logging strategies. This library implements the PSR 3 interface that you can type hint against in your own libraries to keep a maximum of interoperability. You can also use it in your applications to make sure you can always use another compatible logger at a later time. As of 1.11.0…
read the full monolog overview →
About Logstash
Logstash Logstash is part of the Elastic Stack along with Beats, Elasticsearch and Kibana. Logstash is a server side data processing pipeline that ingests data from a multitude of sources simultaneously, transforms it, and then sends it to your favorite "stash." (Ours is Elasticsearch, naturally.). Logstash has over 200 plugins, and you can write your own very easily as well. For more info, see Documentation and Getting Started You can find the documentation and getting started guides for Logstash on the elastic.co site For information about building the documentation, see the README in Downloads You can…
read the full Logstash overview →
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Frequently asked questions
Is monolog or Logstash more popular?
monolog has 21,401 GitHub stars and Logstash has 14,971. monolog has the larger community by that measure.
Are monolog and Logstash free?
Both are open source. monolog is licensed under MIT, and Logstash has no licence declared in this registry. Both are free to self-host.
What is the difference between monolog and Logstash?
monolog is written in PHP and Logstash 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 Logstash?
Choose monolog if you want the larger community (21,401 stars) or its MIT licence terms. Choose Logstash if its feature set, stack or Custom / other licence fits better. Both are self-hostable.