Should unopened peptides go in the fridge or the freezer?

For a short time, the fridge is fine. If you plan to keep the powder for more than a few months before you use it, the freezer is the safer choice. What matters most is a steady temperature. Swinging between frozen and thawed stresses the peptide more than steady cold does.

The whole guide to mixing peptides, step by step, in the order problems come up

Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.

Part of storing unmixed (lyophilized) peptides. How to store the freeze-dried powder before you add any water.