Developer: 200 MB data, 10 MB file. Refresh: 1 day. For individual development. Developer Pro: 1 GB data, 1 GB file. Refresh: 1 day. Larger capacity for teams. Partial Copy: Up to 5 GB data with a sample of production data. Refresh: 5 days. Good for testing with realistic data. Full: Full production copy -- all data, metadata, and users. Refresh: 29 days. Expensive; for final UAT/load testing. All sandboxes append sandbox name to login URL: login.salesforce.com → test.salesforce.com.