How many 25 mg iron bisglycinate capsules should be taken to equal 325 mg ferrous sulfate?

Slight difference: The iron bisglycinate is different form of iron from ferrous sulfate but when studies have been done there is not that much difference in the outcomes but the studies vary a great deal. Some studies show half the amount equals the ferrous sulfate so 175 mg of iron bisglycinate could do the same as 325mg of ferrous sulfate. However both will help iron deficiency. This not proven standard. Hope help