Instant · Precise · Universal
34 units available
6 categories total
To convert Pg to tonnes: multiply by 10⁹. To convert Pg to Tg: multiply by 1,000.
1 Pg = 10¹⁵ g = 10¹² kg = 10⁹ tonnes = 1 gigatonne.
For example, 1 Petagram (Pg) = 5.000000e+15 Carat (ct).
| Petagram (Pg) | Carat (ct) |
|---|---|
| 0.1 | 5.000000e+14 |
| 0.5 | 2.500000e+15 |
| 1 | 5.000000e+15 |
| 2 | 1.000000e+16 |
| 5 | 2.500000e+16 |
| 10 | 5.000000e+16 |
| 25 | 1.250000e+17 |
| 50 | 2.500000e+17 |
| 100 | 5.000000e+17 |
| 500 | 2.500000e+18 |
| 1000 | 5.000000e+18 |
The petagram equals 10¹⁵ grams or one billion tonnes (one gigatonne).
1 Pg = 10¹⁵ g = 10¹² kg = 10⁹ tonnes = 1 gigatonne.
To convert Pg to tonnes: multiply by 10⁹. To convert Pg to Tg: multiply by 1,000.
Global carbon budgets: about 10 Pg of carbon are emitted annually from fossil fuels.
The total mass of all life on Earth is estimated at about 550 Pg of carbon.
Confusing Pg (petagram = 10¹⁵ g) with PB (petabyte). In mass contexts, P = peta = 10¹⁵.
1 Pg C = 1 gigatonne of carbon. Annual human CO₂ emissions are about 10 Pg C — a key climate figure.
The carat is a unit of mass used for gemstones and pearls, equal to exactly 200 milligrams (0.2 grams).
1 ct = 0.2 g = 200 mg = 0.007055 oz.
To convert carats to grams: multiply by 0.2. To convert grams to carats: multiply by 5.
Diamond grading and pricing, gemstone trade, pearl classification, and jewelry appraisal.
The Hope Diamond weighs 45.52 ct (9.1 g). The Cullinan Diamond, the largest gem-quality rough diamond ever found, was 3,106 ct (621 g).
Confusing carat (ct, mass) with karat (K, gold purity). 24K gold is pure gold; a 24-carat diamond weighs 4.8 g.
Carat = weight of a gem. Karat = purity of gold. They sound the same but measure completely different things.



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