Most national central banks provide official daily rates. These are often considered the "gold standard" for legal and accounting purposes.
Are you looking at the price to buy, the price to sell, or the average of both? Most historical databases provide the mid-market rate. download historical currency exchange rates
Offers a user-friendly interface to select specific date ranges and download data directly to Excel. How to Download Data: Step-by-Step Using Excel or Google Sheets Most national central banks provide official daily rates