Customize Default Configuration in Spring Boot | 5 Proven Ways

Learn how to override and customize Spring Boot’s default configuration using properties, custom beans, profiles, and auto-configuration exclusions.

Introduction

Spring Boot offers opinionated defaults that make setup fast. But what if you need different settings?

The good news: Spring Boot lets you override or extend these defaults easily — without disabling everything.

Let’s explore 5 common and powerful ways to customize Spring Boot’s default configuration.

🔹 1. Customize with application.properties or application.yml

This is the most common way to tweak default values.

🔧 Example: Change server port

server.port=9090

🔧 Example: Configure datasource

spring.datasource.url=jdbc:mysql://localhost:3306/mydb
spring.datasource.username=root
spring.datasource.password=secret

📌 Use this for:

• Server settings
• DB connections
• Logging
• Caching
• JPA & Hibernate settings