Pricing for ADF pipelines depends primarily on two factors: the number of activities being run and the volume of data being moved.
How many activities do your pipelines run?
Activities that run on the Azure IR are a bit cheaper than those run on the Self-Hosted IR.
How much data do you move?
You pay by the hour for the compute resources used for data movement, e.g., the data moved by a Copy activity.
As with activities, the prices for data movement with the Azure IR vs. the Self-Hosted IR differ (although, in this case, using the SelfHosted IR is cheaper). You will also incur the standard charges for moving data from an Azure data center.
It’s also worth noting that you’ll be charged separately for any other Azure resources your pipeline uses, such as blob storage or a Spark cluster.
For current details on ADF pipeline pricing, see here.