apps and api


Request container tare weight effortlessly to meet SOLAS VGM requirements.

Category Container | ESG & Compliance | Land | Ports
Developer ContainerWeight

Since July 1st 2016, every packed container to be loaded on board of a SOLAS ship needs to have its Verified Gross Mass determined. Determining the weight can be done through Method 1 (weighing the packed container using calibrated and certified weighing equipment) or through Method 2 (calculation: container tare weight + weight of the goods; which requires a special permission). When using Method 2 it is crucial for al shippers to have access to the correct tare weight of all shipped containers.

The shipper provides the verified weight to the shipping agent, who passes it on to the carrier (who needs to balance the vessel), and to the terminal (who is not allowed to load the container without the information). Several other parties could also benefit from having the weight in their digital files, e.g. CMR documents.

By calling the VGM Tare Weight API with the correct container number both the tare weight and the container ISO code can be accessed. Our partner for this API claims a 99% coverage of the current global container fleet. The API makes that none of your employees must leave their desk to record the tare weight of a box.

Be compliant
Be compliant with laws & regulations and always provide accurate weight information.

Centralised weight
Single truth for the VGM (Verified Gross Mass) of a container.

Operational efficiencies
Knowing the weight of a container helps organizing the supply chain.

Possible users of this service are all shippers that export containers that should be loaded under the SOLAS regulation.

The API provides both the tare weight of any container and if requested also the ISO-code. Request-key is the container number.

In order to use this API


Upon request

Max 99 calls every 5 minutes *

Pricing is based on a token system, Each time the weight or ISO-number is called using the API a token is subtracted from a digital wallet. Tokens are prepaid and added to your wallet.
The price of tokens decreases depending on the purchased amount. To obtain more specific details or a quote contact the NxtPort team.

* The general yearly NxtPort subscription fees apply when subscribing to this or any other API on the NxtPort platform.

ContainerWeight is the owner of the information returned via the API and maintains the accuracy and completeness of the data. NxtPort provides data-users the supports the integrating and contracting with ContainerWeight through its data platform. Should you encounter problems during or after the integration, you can contact NxtPort support.

Other companies that are interested in sharing their data on the NxtPort platform, can contact us.

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This API is a direct access API.

This means that the data is not under specific sharing control and that there is no need to implement a full authentication flow. The only thing you need is an API key to add to the header of your API call. You can get that key by subscribing to the API. API usage is metered and billed based on this API key. If usage should be billed to the users of your application, you should ask those users to bring their own key.


All required information can be found on Github. We chat through #slack.