This half life reference table shows the quantity remaining for a range of initial quantity values, assuming a half-life of 5 and an elapsed time of 10. Every figure is computed with the same engine that powers our Half Life Calculator, so the numbers are exact.
| Initial quantity | Quantity remaining | Number of half-lives |
|---|---|---|
| 25 | 6.2500 | 2.00 |
| 50 | 12.5000 | 2.00 |
| 75 | 18.7500 | 2.00 |
| 100 | 25.0000 | 2.00 |
| 150 | 37.5000 | 2.00 |
| 200 | 50.0000 | 2.00 |
| 300 | 75.0000 | 2.00 |
| 500 | 125.0000 | 2.00 |
| 700 | 175.0000 | 2.00 |
| 1,000 | 250.0000 | 2.00 |
How to use this table
Find the row closest to your initial quantity and read across to the quantity remaining. For a value between two rows, the real figure sits between them — or enter your exact numbers in the Half Life Calculator for a precise answer.
Need a value that is not in the table? — the Half Life Calculator does it instantly, for free, with the formula and a worked example built in.
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