Apex Classes is the Setup page where Apex code lives — class metadata, version, status (Active / Deprecated), test coverage. Most modern orgs deploy Apex via DX or Change Sets, not the Apex Classes Setup page directly. The page is mostly for review and quick edits.
- Open Setup → Apex Classes
Setup gear → Quick Find: Apex Classes → Apex Classes.
- Review the list of classes
Each row: Name, Last Modified, Status, API Version, Lines of Code (read from Modified Source).
- Click New for in-Setup class creation (rare)
Most code is deployed from outside Setup. The New button creates a class via the inline editor — fine for tiny utility classes, awkward for real development.
- Click into a class for source
Source code, with Compile errors highlighted if any. Edit inline (in production this requires Modify Metadata permission).
- For test coverage: click Test → Run Tests
Runs the test methods on this class. Coverage shown in real time.
- For dependency analysis: click Show Dependencies
Lists what other metadata references this class — useful before deletion.
What version of the Salesforce API the class targets. Older versions get fewer Salesforce features.
Active (deployed and running) / Deprecated (callable but flagged for removal).
Surface inline. Deploy fails if any Apex Class has compile errors.
- Editing Apex inline in Setup → Apex Classes is allowed in sandboxes by default but requires the Modify Metadata permission in production. Many orgs lock this down.
- Renaming an Apex class is a destructive operation. References to the old name break — rename via deploy with a careful migration path.
- API Version locks features available to the class. A class on API 30 can't use Modern Apex features (System.JSON improvements, etc.). Bump to current API only after testing.