What was a guilder worth?

Guilder is the English translation of the Dutch and German gulden, the term that became current in the southern and western parts of the Holy Roman Empire for the florin that was introduced in 1252. Guilder has often been interchangeable with florin (currency sign ƒ. or ƒl.). Learn more at Wikipedia's Dutch Guilder.

Given the differences brought by the Industrial Revolution, it is extremely difficult to make any direct comparisons between the purchasing power of money in Leeuwenhoek's Delft and in our lives today. Clothing for example, was much more expensive in his time, but it lasted so long that people bequeathed it to their heirs.

The Historic Currency Calculator (no longer available) at DutchAncestryCoach.com returned the following results in 2013:

  • 314 guilders in the year 1660 was equivalent to 1.1 yearly wages of an unskilled worker. This roughly corresponds to 29,927 USD today.
  • 5,000 guilders in the year 1655 was equivalent to 18.3 yearly wages of an unskilled worker. This roughly corresponds to 514,670 USD today.

The International Institute of Social History (IISH) has a calculator that returns different results when queried in mid-2014.

  • 400,000 guilders (about Delft's annual budget) in 1680 has a "purchasing power" of about 4,390,000 EUR  or 5,980,000 USD
  • 5,000 in the year 1680 has a "purchasing power" of 56,927.00 EUR or 77,419 USD

The IISH calculator's standard of about 300 guilders as the yearly wages of an unskilled laborer agrees with the income ranges in Delft during Leeuwenhoek's time. Nevertheless, with results an order of magnitude apart and so much time having passed, it seems clear that we can only roughly estimate the purchasing power of Leeuwenhoek's salary.