I want to get the part with the closest size to a selected part

I have tried to look at other posts but cant find anything that helps me
This is the code i have now, but it dont work:

local selectedPart = workspace.RedBox
local PartsFolder = workspace.PartsFolder
local parts = {
part1 = PartsFolder.Part1,
part2 = PartsFolder.Part2,
part3 = PartsFolder.Part3,
}
local closestPart = nil
for i, part in parts do
if closestPart == nil then
closestPart = parts.part1
else
if selectedPart.Size.X >= part.Size.X and selectedPart.Size.Y >= part.Size.Y and selectedPart.Size.Z >= part.Size.Z then
closestPart = part
end
end
end
print(closestPart.Name)

You could calculate the differences between the X, Y, and Z values between the original part and modified part. Then, you could identify the which is closest by identifying the part with the smallest difference.

For example, let’s say the original part is 1 by 1 by 1, and then we’ll have 3 other parts similar to that part:

Original Part - (1, 1, 1)

Part A - (1.5, 1.5, 1.5)

Part B - (0.25, 0.25, 0.25)

Part C - (5, 5, 5)

You will have to find the difference of each value by subtracting it to the original part value. Once you calculate that, you determine which one has the lowest difference, and in this case, that would be Part A, because the difference of all values are 0.5, which is the lowest compared to Part B, 0.75, and Part C, 4.

With that in mind, we can modify your script to do this. I tested this myself in studio, and it worked perfectly everytime.

local selectedPart = workspace.RedBox
local PartsFolder = workspace.PartsFolder
local parts = {
part1 = PartsFolder.Part1,
part2 = PartsFolder.Part2,
part3 = PartsFolder.Part3,
}
local closestPart = nil
local partDifferences = {}
for i, part in parts do
local differenceInX = math.abs(selectedPart.Size.X - part.Size.X)
local differenceInY = math.abs(selectedPart.Size.Y - part.Size.Y)
local differenceInZ = math.abs(selectedPart.Size.Z - part.Size.Z)
local absoluteDifference = differenceInX + differenceInY + differenceInZ
table.insert(partDifferences, {part, absoluteDifference})
end
table.sort(partDifferences, function(a, b)
return a[2] < b[2]
end)
closestPart = partDifferences[1][1]
print(closestPart)