Your tow vehicle has to do more than just pull the weight of a trailer. On average the tow vehicle is actually carrying up to fifteen percent of the loaded trailer weight. It must also carry the weight of everybody and everything you put in or on it.
You can calculate the max loaded trailer weight by looking at the tire / loading sticker on your drivers door. It will show a number for max occupant / cargo weight (AKA payload). That is the tow vehicle's max carrying capacity. From your payload number, subtract 100 lbs for a weight distributing hitch (if needed), subtract the weight of your family, and subtract the weight of things you would normally carry in or on the vehicle. What you have left is available to carry loaded trailer tongue weight. Diivide that by .13, to get a ball park of loaded trailer weight that will put you at max weight.
Example
Say your payload is 1400 lbs, family weight is 500 lbs, WD hitch is 100 lbs, and you have 200 lbs of additional cargo. Your available payload would be 600 lbs (1400-500-100-200 = 600). Six hundred pounds divided by .13 would be 4615 lbs of loaded trailer weight.
Average camping load (dishes, pots and pans, camping gear, groceries, bedding, and water) being 800 to 1000 lbs. You would be looking at trailers with unloaded (dry) weights around 3700 lbs.