# Spring Boot 4.1.1 + Tomcat 11.0.x — Software interface version compatibility

For Spring Boot 4.1.1 + Tomcat 11.0.x, product is Spring Boot; software version is 4.1.1; dependency version is Tomcat 11.0.x; companion package versions is Servlet 6.1, recorded from its source on 2026-08-27; source re-checked 2026-10-28.

- **Product:** Spring Boot _(our reading, not quoted from the source)_
- **Version pairing:** Spring Boot 4.1.1 + Tomcat 11.0.x _(our reading, not quoted from the source)_
- **Software version:** 4.1.1
- **Dependency version:** Tomcat 11.0.x _(verified: appears in the quote below)_
- **Companion package versions:** Servlet 6.1

## What the source says

> Tomcat 11.0.x | 6.1 |

## Source

- https://docs.spring.io/spring-boot/system-requirements.html

Last verified: 2026-10-28. Review by: 2026-12-27.
Part of [Software interface version compatibility](https://referencesource.org/software-interface-version-compatibility/).