Since hops are generally harvested when the moisture content is between 75% and 78%, you should only need to multiply the dried hop weights in your recipe by 3.5 to 4 to get the wet hop bittering effect equivalent (assuming roughly equal alpha percentages).
If the wet hops have been in the sun for a few hours or in a warm room for a day or two, more moisture will have evaporated, so the conversion factor may be closer to 3 than 4.
If the alpha acid percentages for your wet hops and typical dry hops are about equal, multiply the dry weight in the recipe by the appropriate conversion factor to see how many ounces of wet hops you need.
When hops are harvested they are very moist. In fact, about 75% of their weight is water, hence the term “wet hops” for hops fresh from the bine. However, before hops can be packaged or pelletized, they have to be dried down to between 8% and 12% moisture content. Hops with a moisture content above 12% are likely to mildew and oxidize, while hopes dried below 8% lose essential oils and tend to shatter during packaging and processing, resulting in the loss of lupulin as well.
The alpha acid percentages brewers are used to seeing (i.e., those reported on the packages of hops pellets or dried whole leaf hops you buy) are based on the dried hops values, not the values when the hops were first harvested. Alpha percentages for wet hops are much lower, but as shown in the Alpha Acids table, there is a simple formula for converting wet hops percentages to percentages based on the more familiar 10% Moisture Content (MC) samples.
If the alpha acid % for the wet hops (based on 10%MC) is similar to the alpha % of the hops your recipe calls for, you can use the table below to determine how to convert dried hop weights to wet hop weights. As the table illustrates, the moisture content of the wet hops is the primary determinant of the conversion factor. If you google this question, you’ll find some websites saying that in order to get the same bittering effect you need 5 to 6 times more wet hops than dry hops. This is seldom the case, however, unless you're getting very early less mature harvests.