for iPhone and iPad Touch

ChemWeight is a high-quality molecular weight calculator for the iPhone and iPod Touch.

With ChemWeight, you can enter chemical formulas using a convenient, customizable keypad. The keypad format makes formula entry simple and quick. (Infrequently entered symbols are accessed from a pop-up list.)

Both atomic symbols and common organic group symbols can be used to construct formulas. Elements 1 through 118 and deuterium are available, along with eighteen common organic substituents and protecting groups.

You can choose to use either average or monoisotopic atomic weights. In addition to the molecular weight, a tap of the screen reveals the chemical composition (percent by weight) and total atom counts.

If you need to calculate molecular weights for oligonucleotides or peptides in addition to small molecules, you might consider our alternative app, MolWeight, which calculates other useful macromolecular properties in addition to molecular weight.