# Can Shipping Cost Calculation Work For Products With Options?

Product variants often have very different weights. For example:

Product A

• option 1: 20 grams
• option 2: 3 kg

Depending upon the shipping method and destination the shipping costs of option 1 and option 2 can differ up to \$200. If the customer would have to pay \$200 to much for option 1 then no one will buy it.

We can only set one weight per product. Not per option. So how can we have correct shipping costs calculation?

There is option variant weight modifier.

Thanks!

How does the option variant modifier work? For example;

option 1 = 250grams

option 2 = 3000grams

Do I add option 1 to option variant weight modifier and leave the shipping properties of the main product as 0?

Option 2 needs to be added to option variant weight modifier. But how?

option 2 = 3000grams

For option 2 do I add 3000-250=2750grams?

Or do I add 3000 grams?

I believe, like price modifiers, that it is additive. I.e. if you have base product at 100g and option 1 at 20g and option 2 at 40g that selecting option 2 gives you a total weight of 140g.

And if you do not fill in a base weight for the main product then the base weight will be 0? And from there option 1 can be +120 grams for option 1 and +140grams for option 2? So that selecting option 2 will give a weight of 140 grams?

don't know for sure, but would assume so. Though it's also possible that a zero weight says to skip something too.

Pretty easy to just try it on a test product and see what it doesâ€¦ You might have to add some instrumentation to get the actual weight used for the shipping rate since that's not usually shown in any of the dialogs.

I can get that from the http request.

It works to set the main weight to 0 and then the modifer to the real weight. Thats great. There is some deviation between the real weight and the output sent to the shipper, but its minimal. Seems a bug though.

I'd guess a bug, but maybe they add something for packagingâ€¦?