# Migrating from MMDetection 2.x to 3.x

MMDetection 3.x is a significant update that includes many changes to API and configuration files. This document aims to help users migrate from MMDetection 2.x to 3.x.
We divided the migration guide into the following sections:

- [Configuration file migration](./config_migration.md)
- [API and Registry migration](./api_and_registry_migration.md)
- [Dataset migration](./dataset_migration.md)
- [Model migration](./model_migration.md)
- [Frequently Asked Questions](./migration_faq.md)

If you encounter any problems during the migration process, feel free to raise an issue. We also welcome contributions to this document.