Can I add decimal quantity increments?
WooCommerce itself is built around the idea that customers will only ever order quantities in whole numbers. As a result, we have built WooCommerce Quantity Manager to only support whole numbers for quantity increments and step values.
For simple WooCommerce stores, it may be possible to get decimal quantities working correctly. However, this can cause problems when you connect your store with third party systems such as payment gateways and shipping providers, which may not support decimal quantity values.
As a result, this feature is not available in WooCommerce Quantity Manager because of the way it works with the standard WooCommerce quantity input field. Instead, we have a different plugin - WooCommerce Product Options - which lets you add a different type of quantity picker and does support decimal quantities. You can add min/max quantities to the decimal quantity field.
We have written a step-by-step tutorial about how to set this up. The end result might look something like this: