Convert Ounce (oz) to Petagram (Pg) instantly.
About these units
Ounce (oz)
The ounce is a unit equal to 1/16 of a pound, or approximately 28.3495 grams, with roots in ancient Roman "uncia"—one-twelfth of a pound. The ounce is used for measuring small masses in cooking, postal services, gemstones (troy ounces), and various consumer goods. Despite not being part of the metric system, the ounce remains a staple in US everyday life, from food packaging to hardware components. Its small size gives it a practical niche where grams might feel too unfamiliar for some audiences. Multiple ounce variants exist historically—avoirdupois, troy, apothecary—but the avoirdupois ounce is now the standard in general commerce. Its endurance reflects the cultural weight of imperial units and the long history of Western measurement systems.
Petagram (Pg)
A petagram, equal to 10¹² kilograms, is used almost exclusively in global environmental science and earth system modeling. Planetary-scale carbon budgets—for example, the total carbon stored in Earth's soils or forests—are expressed in petagrams. The Amazon rainforest alone holds on the order of 100 Pg of carbon. Using petagrams helps researchers track changes in Earth's climate balance and evaluate feedback loops in the carbon cycle.