系统内冗余或重复数据的度量，表明存储和潜在性能问题效率低下。
1 FDR = 1.333 HC
1 HC = 0.75 FDR
例子:
将15 频级冗余转换为锤子代码冗余：
15 FDR = 20 HC
| 频级冗余 | 锤子代码冗余 |
|---|---|
| 0.01 FDR | 0.013 HC |
| 0.1 FDR | 0.133 HC |
| 1 FDR | 1.333 HC |
| 2 FDR | 2.667 HC |
| 3 FDR | 4 HC |
| 5 FDR | 6.667 HC |
| 10 FDR | 13.333 HC |
| 20 FDR | 26.667 HC |
| 30 FDR | 40 HC |
| 40 FDR | 53.333 HC |
| 50 FDR | 66.667 HC |
| 60 FDR | 80 HC |
| 70 FDR | 93.333 HC |
| 80 FDR | 106.667 HC |
| 90 FDR | 120 HC |
| 100 FDR | 133.333 HC |
| 250 FDR | 333.333 HC |
| 500 FDR | 666.667 HC |
| 750 FDR | 1,000 HC |
| 1000 FDR | 1,333.333 HC |
| 10000 FDR | 13,333.333 HC |
| 100000 FDR | 133,333.333 HC |
规则