Welcome to the SBO forum
@cefiro . I see you have been looking at boats. It is a noble quest.
Perhaps understanding the nature of boats might help.
@sail sfbay has given you the links to Sailboat Data. You can look at the numbers. Displacement is not the only element to compare. It is not like a car. ("Hey get the big Caddie. They are all steel and weigh in like a ton")
There is a lot more to being comfortable on a boat sailing or cruising or racing.
On the SailboatData site there is "Definitions" link. Hre is the info it shares regarding the numbers printed.
Calculations Help
SA/Disp.:
A sail area/displacement ratio below 16 would be considered under powered;
16 to 20 would indicate reasonably good performance;
above 20 suggests relatively high performance.
SA/D = SA (ft²) ÷ (Disp (lbs) / 64)^.666
Bal./Disp.:
A Ballast/Displacement ratio of 40 or more translates into a stiffer, more powerful boat that will be better able to stand up to the wind.
Bal./Disp = ballast (lbs)/ displacement (lbs)*100
Disp./Len.:
The lower a boat's Displacement/Length (LWL) ratio, the less power it takes to drive the boat to its nominal hull speed.
less than 100 = Ultralight;
100-200 = Light;
200-275 = Moderate;
275-350 = Heavy;
350+ = Ultraheavy;
D/L = (Disp / 2240) / (0.01*LWL)^3.
Comfort Ratio:
This is a ratio created by Ted Brewer as a measure of motion comfort. It provides a reasonable comparison between yachts of similar size and type. It is based on the fact that the faster the motion the more upsetting it is to the average person. Consider, though, that the typical summertime coastal cruiser will rarely encounter the wind and seas that an ocean going yacht will meet.
Numbers below 20 indicate a lightweight racing boat;
20 to 30 indicates a coastal cruiser;
30 to 40 indicates a moderate bluewater cruising boat;
40 to 50 indicates a heavy bluewater boat;
over 50 indicates an extremely heavy bluewater boat.
Comfort ratio = D ÷ (.65 x (.7 LWL + .3 LOA) x Beam^1.33), where displacement is expressed in pounds, and length is expressed in feet.
Capsize Screening Formula (CSF):
Designed to determine if a boat has blue water capability. The CSF compares beam with displacement since excess beam contributes to capsize and heavy displacement reduces capsize vulnerability. The boat is better suited for ocean passages (vs coastal cruising) if the result of the calculation is 2.0 or less. The lower the better.
CSF = Beam/Disp (cubic ft)^.333. The displacement in cubic feet can be found by dividing the displacement in pounds by 64.
S#:
S# first appeared (that we know of) in TellTales, April 1988, “On a Scale of One to Ten” by A.P. Brooks . The equation incorporates SA/Disp (100% fore triangle) and Disp/length ratios to create a guide to probable boat performance vs. other boats of comparable size. For boats of the same length, generally the higher the S#, the lower the PHRF.
Under 2 - Slow, under powered.
2-3 - Cruiser
3-5 - Racer Cruiser
5+ - Fast/Racing
S# = 3.972*(10^(-[@[Dsp/LWL]]/526+(0.691*(LOG([@[SA/Dp]])-1)^0.8)))
You might also find this link to Blue Water boats helpful.
bluewaterboats.org
It gives a little more info about a boat and how it will feel to you when you head out of the bay on to the ocean. You need to start thinking. Even out a few miles from the coastline you are still at "Sea". If it gets rough or a storm cloud pops up over your boat you will be challenged. Get the boat that makes you feel safe, and moves you too buy it. Going on a little cruise to the Bahamas is a lot like heading East to the Mediterranean Sea. It is just a little further but both can be dangerous in a small boat.