Step 1: Mohenjodaro's extent: Mohenjodaro, the largest known Harappan city, spread over roughly 200 hectares (about 2 square kilometres), making it one of the most extensive Bronze Age urban sites in the world.
Step 2: Chanhudaro's extent: Chanhudaro was far smaller, covering only about 5 hectares — consistent with its role as a specialised craft-production centre rather than a major administrative city.
Final Answer: Mohenjodaro ≈ 200 hectares; Chanhudaro ≈ 5 hectares.