In, on and at narrow from largest to smallest: in an area, on a surface or line, at a point.

One rule generates almost all of place and time. A country is an area you are inside; a road is a line you are along; a house number is a point with no extent.

She lives in Kanpur, on Mall Road, at number 14.

area, then line, then point

She lives at Kanpur, in Mall Road, on number 14.

the three scales are swapped

Where it bites

Where the noun could be read either way. 'In the office' is the space, 'at the office' is the workplace as a point on your day — both correct, and the sentence decides which.