A Tech Research Calculator, enjoy.
If you haven't yet got/combined the unit you are pulling for and can make 250 pulls it is highly recommended that you do not combine the unit from the shards you get. At 250 pulls you get a 3* UR guaranteed (equivalent of 70 shards) which gets converted to 28 shards if you already own the unit.
If you already have the unit you are pulling for, you can enable advanced mode and specify how many stars and shards you have. The calculator will take care of the rest.
Other guaranteed rewards include Emblem or Tome every 100 pulls, Orange War Soul every 150 pulls and Weapon every 200 pulls.
Disclaimer: calculator is based on probability theory and expectation values. The calculated reward values represent what a large number of players will get as an average for a given number of pulls.