Scope: This is the most common and general term for the extent of a project. It refers to the overall goals, deliverables, and boundaries of the project.
Magnitude: This refers to the size or scale of the project, often in terms of its complexity, resources required, or impact.
Reach: This refers to the impact or influence of the project, particularly on its intended audience or stakeholders.
Duration: This refers to the length of time the project will take.
Budget: This refers to the financial resources allocated to the project.
Complexity: This refers to the level of difficulty and intricacy involved in completing the project.
Ambit: This is a more formal word that refers to the range or scope of the project, often emphasizing its breadth or ambitious nature.
Breadth: This refers to the wide range or scope of the project, encompassing various aspects or areas.
The best word to use will depend on the specific context and the aspect of the project you wish to emphasize.