Query Studio:

1. Used to create Ad-hoc (or) simple reports.

2. It does not provide any pre-defined report templates.

3. It directly displays data (without running the report) when we insert attributes in the report.

Report Studio:

1. Used to create complex reports.

2. It provides pre-defined report templates.

3. It does not display the data directly in the report. We need to run the report to display the data.