Activate WooCommerce, DK Base Plugin, and DK WC Class Based Shipping. Open WooCommerce > Settings > Shipping, edit the appropriate shipping zone, and add Class Based Shipping as a shipping method. Configure each zone's method separately.
Enable the method, set its customer-facing title, and choose whether the rate is taxable. Create shipping classes in WooCommerce and assign them to your products or variations before configuring their rules.
Each shipping class, plus No shipping class, has its own calculation type: Disabled, Weight based, or Quantity based. New rules are disabled. Selecting a type reveals its relevant fields. Rate note and Rate date are administrative reference fields; they do not affect the calculation.
Set Base cost, Included weight (lbs), Weight step (lbs), and Step cost. The plugin totals the shipping products in that class, including their quantities, and converts WooCommerce's configured weight unit to pounds.
Up to the included weight, the charge is the base cost. Above it, each started weight step adds the step cost: base + ceil((weight - included weight) / step) × step cost.
A base cost of 5, included weight of 1 lb, step of 1 lb, and step cost of 0.75 charges 6.50 for 2.2 lbs. Two additional steps are required. Enter amounts in the store's currency.
Missing product weights count as zero. A step of zero or less results in the base cost only, so use a positive step for incremental weight pricing.
Quantity based rules use base cost + quantity cost × class quantity. A base of 2 and quantity cost of 4 charges 14 for three items in that class.
For each WooCommerce shipping package, the plugin groups products by shipping class and adds the enabled class charges together into one shipping rate. Base costs apply once per class group in that package. Products that do not need shipping are ignored.
Disabled classes contribute no charge. If every class in the package is disabled, this method returns no rate. An enabled rule whose calculated cost is zero can return a zero-cost rate. Configure every class that needs a charge, including No shipping class.
Check the customer's matching shipping zone, the method's enabled setting, and the rules for the products actually in the package. At least one matching class rule must be enabled.
Review variation shipping classes, product quantities, weights, and the store's weight unit. Remember that partial weight steps round upward and separate class groups each have their own base cost. Shipping tax is added according to WooCommerce's tax configuration.
Test a cart containing one class, then a mixed-class cart and a product with no class. Refresh shipping calculations after saving changes. Other shipping methods in the zone may still provide additional choices.