A wonderful page of interesting tables and charts showing how Consumer Price Index (CPI) affects prices and nearly everything else that has money as a base. There are conversion factors to determine the value of dollars of the years 1774 to estimated 2028 in dollars of the years 2018, 2017,2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2008 ,2007, 2006, 2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998, 1997, 1996, and 1995. Plus lots more.  Note: As of July 16 2021 data hs not been updated since August 14 2018. 

Open Access

https://liberalarts.oregonstate.edu/spp/polisci/research/inflation-conversion-factors

Lots of information about foreign exchange including a converter. The converter lets you convert between any two of the worlds currencies. For example you can determine how many Yen, Pounds, or Krone you can get for your Dollar, Peso, or Franc? You can find the conversion rate for any day or range of days from January 1990 through yesterday. There are also links to a large number of currency trading information sites.

Open Access

https://www1.oanda.com/currency/converter/

A collection of financial calculators including their Universal Currency Converter for converting more than 180 world currencies in to any other world currencies and a Credit Card Charges Calculator that it will give you an estimate of the “hidden” charges the credit card issuer is adding on for converting the foreign exchange and processing the transaction.

Open Access

https://www.xe.com/