# Get shipping weight before confirming sale
**URL:** https://discuss.tryton.org/t/get-shipping-weight-before-confirming-sale/8777
**Category:** User
**Tags:** stock, sales
**Created:** [August 17, 2025, 2:34pm UTC](https://discuss.tryton.org/t/get-shipping-weight-before-confirming-sale/8777 "2025-08-17T14:34:13Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@dotbit](https://discuss.tryton.org/u/dotbit)
#### Post date: [August 17, 2025, 2:34pm UTC](https://discuss.tryton.org/t/get-shipping-weight-before-confirming-sale/8777/1 "2025-08-17T14:34:13Z")
I often find myself having to calculate the weight of many items manually in order to calculate/get carrier quotation for the shipment.
Then I use this information to set the shipping price of the order, in order to have the invoice with the right shipping cost.
You say: confirm the order, set invoice method to manual, update the shipping cost on the shipment, and then make the invoice manually. The issue here is that I need to have the invoice prepared to give to the driver and it is not practical to prepare the documents just in time: it is better to have the prepared before the driver arrives.
From what I can tell, I can set Shipment cost method: on sale, or on shipment.
I can not set the shipping cost on sale, as I do not know it before calculating the weight and getting the carrier offer.
And I can not use on shipment sent, as I would have to generate the invoice while I am loading the lorry, or make the driver wait.
Also I do not like the idea of “Ship” before actually shipping.
I imagine there are two options: Create the shipment before the sale is confirmed, or have a method to get the shipping weight without creating the shipment.
Also I do not like the idea of using sale\_amendment to modify the shipping cost after the sale is confirmed.
Any ideas how to make this less painful?
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### Author:  [@ced](https://discuss.tryton.org/u/ced)
#### Post date: [August 18, 2025, 7:35am UTC](https://discuss.tryton.org/t/get-shipping-weight-before-confirming-sale/8777/2 "2025-08-18T07:35:10Z")
Ideally you should be able to make Tryton compute the shipping cost with [Carrier Weight Module — Tryton module to add cost method "on weight" on carrier](https://docs.tryton.org/latest/modules-carrier-weight/index.html) .