When looking through old French records, you will frequently come across old measurements that are rather mysterious nowadays. These measurements are found in records originating in France, Quebec and Louisiana. Below is a table showing the equivalencies, but many online sites offer conversion calculators, even for these old standards.
Conversion Table for Old French Units of Measurement
| Old French Units of Measurement | Conversion to Other Units of Measurement | |
|---|---|---|
| 1 pied | 0.324 837 81 metres | 1.065 740 34 feet (English measure) |
| 1 toise | 6.0 pieds | 1.949 026 87 metres
6.394 442 03 feet (English measure) |
| 1 perche | 3.0 toises | 18.0 pieds
5.847 080 62 metres 19.183 326 1 feet (English measure) |
| 1 arpent | 10.0 perches | 30.0 toises
180.0 pieds 58.470 505 4 metres 191.833 261 feet (English measure) 63.944 420 3 yards (English measure) |
| 1 lieue | 84.0 arpents | 840.0 perches
2 520.0 toises 15 120.0 pieds 4 911.547 72 metres 4.911 547 72 kilometres 16 114.0 feet (English measure) 5 371.333 33 yards (English measure) 3.051 893 94 miles (English measure) |
| 1 arpent carré | 32 400.0 pieds carrés | 3 418.80 square metres
0.341 88 ares 36 800.0 square feet (English measure) 0.844 803 06 acres (English measure) |
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