ppm and ppt are defined as:
1ppm = 1/106 = 10-6
1ppt = 1/1012 = 10-12
So
1ppm = 106ppt
The number of parts-per trillion xppt is equal to the number of parts-per million xppm multiplied by 106:
xppt = xppm ⋅ 106
Example: 7ppm is equal to 7000ppb:
xppt = 7ppm ⋅ 106 = 7000000ppt
| ppm | ppt |
|---|---|
| 0.000001 | 1 |
| 0.00001 | 10 |
| 0.0001 | 100 |
| 0.001 | 1000 |
| 0.01 | 10000 |
| 0.1 | 100000 |
| 1 | 106 |
| 10 | 107 |
| 100 | 108 |
| 1000 | 109 |
| 10000 | 1010 |