1, the difference: cpi mainly focuses on the price changes of goods and services purchased by consumers, including food, housing, transportation, education, medical care and other fields, while ppi mainly focuses on the price changes of goods and services purchased by enterprises, especially raw materials, fuel and power in industrial production.

2. Connection: ppi changes are often transmitted to cpi, because the increase in production costs will eventually be reflected in the goods and services purchased by consumers. This price transmission relationship makes ppi an important indicator to predict cpi changes.

3.cpi, the full name of consumer price index, is a macroeconomic indicator reflecting the price changes of consumer goods and services purchased by households. It is mainly used to measure the total cost of consumers buying a certain number of goods and services, and to measure the level of inflation.