25 parts-pm = 0.025 parts-pb. To convert parts-per million to parts-per billion, divide by 1,000: 25 ÷ 1,000 = 0.025.
How to convert parts-per million to parts-per billion
parts-pb = parts-pm × 0.001
- 1 parts-pm = 0.001 parts-pb (and 1 parts-pb = 1,000 parts-pm).
- Multiply the amount by the factor: 25 × 0.001 = 0.025.
- Answer: 25 parts-pm = 0.025 parts-pb.
Shortcut: dividing by 1,000 gives the same result as multiplying by 0.001.
Parts-per Million to Parts-per Billion table
| Parts-per Million (parts-pm) | Parts-per Billion (parts-pb) |
|---|---|
| 20 parts-pm | 0.02 parts-pb |
| 21 parts-pm | 0.021 parts-pb |
| 22 parts-pm | 0.022 parts-pb |
| 23 parts-pm | 0.023 parts-pb |
| 24 parts-pm | 0.024 parts-pb |
| 25 parts-pm | 0.025 parts-pb |
| 26 parts-pm | 0.026 parts-pb |
| 27 parts-pm | 0.027 parts-pb |
| 28 parts-pm | 0.028 parts-pb |
| 29 parts-pm | 0.029 parts-pb |
| 30 parts-pm | 0.03 parts-pb |
| parts-pm | parts-pb |
|---|---|
| 1 parts-pm | 0.001 parts-pb |
| 5 parts-pm | 0.005 parts-pb |
| 10 parts-pm | 0.01 parts-pb |
| 50 parts-pm | 0.05 parts-pb |
| 100 parts-pm | 0.1 parts-pb |
| 1,000 parts-pm | 1 parts-pb |