Rating’ was a system of classifying warships. It originally referred to the rates of pay of their captains but by the late-17th century the Rate was calculated by the number of guns a ship carried.

The ships of the line were the First to Fourth Rates.

Although some ‘re-rating’ occurred, the general system was:

* First Rate – ships of 100 guns (later also 104, 110 and 120 guns)

* Second Rate – ships of 90 guns (later 98 guns)

* Third Rate – ships of 80, 74, 70 and 64 guns

* Fourth Rate – ships of 60 and 50 guns

* Fifth Rate – ships of 44, 40, 38, 36 and 32 guns

* Sixth Rate – ships of 28, 24 and 20 guns

From the early 18th century vessels of less than 20 guns were not rated. First Rates of more than 100 guns were developed only at the very end of the 18th century.

Source: NMM