What is the difference between Material Planning and purchasing?

Material Planning refers to the budgeted plan of procurement for a list of equipments and materials with its order, manufacturing and delivery forecasted dates for a approved list of vendors against specific projects whereas purchasing is one time action of purchase which may be planned or unplanned

 Planning  material is trying to identiy the material I needed, criterias, when I need it . An inportant decision should be taken whether to make it or buy decision, this is part of planning  processes.  

Purchsing is execution process (conduct procurements) the steps should be done to acquisite the requested item or items

Material planning is an ongoing process that refers to understanding ALL the requirements for a specific commodity over a known time period, taking into considration ALL factors that may impact the planned outcome.

Purchasing refers to the ongoing management of vendors and service providers to ensure the best financial position for the organisation, quality of goods or services obtained, and reliability of supply or service delivery.

Material planning is primary stage of purchasing . In different kinds material inventory firstly calculate MRP and depends on that  making procurement delivery schedules.

material planning starts at the start of a project. we decide in it what kind of material we are required considering the specification, when we required and in how much quantity we required. this is the responsibility of the planning department and then the plan is send to the procurement for the material purchasing.

Agreed with expert opinions

Material planning will refer to a specific event or project. Purchasing will be generic in nature and will be system driven based on consumption data.

Material planning will be costed to the project or event, whereas purchasing will in most cases be costed against 'Cost of Sales'