If you have a question for which you can’t find an answer here, or if have suggestions for missing features, you can contact us.

Can I use FTP?

No, you can no longer use FTP to access KDP datasets. With the migration from KDC to KDP, FTP downloads have been replaced by API downloads.

What does the message Access to this API has been disallowed means?

KDP provides an anonymous API key for its customers. Our old anonymous API has expired and is discontinued. You can find a new anonymous API key in the Open Data API documentation. The anonymous API key has a lifecycle of a year, so check the end date carefully. If you don’t want to change your applications yearly, we advise you to look into a registered key.

    "error": "Access to this API has been disallowed"

Why is there a yearly lifecycle for the anonymous API key?

All datasets on this portal are free of charge and are provided under the ‘OpenData’ policy of the Dutch government. We cannot identify the users of the anonymous API key. A lifecycle policy is in place for updating this key every year. This lifecycle policy opens up the possibility for housekeeping for our portal, and enables us to keep providing open and free access. If you don’t want to update the API key yearly you can register an account with an email address. With this account you can register for APIs. This means the key is for you alone and will not be updated yearly.

How can I get my open data files now?

The Open Data API documentation provides you with the required information to access Open Data.

How do I open or use files with the .nc extension?

In KDP context, files with the .nc extension refer to NetCDF files. NetCDF is a data format that supports the creation, access, and sharing of array-oriented scientific data.

There are different libraries in different programming languages that can be used to load and manipulate NetCDF files. Documentation of these libraries describes how the library can be used in combination with NetCDF files.

I have lost my personal API key, what can I do?

If you request an API key, you receive a confirmation email with details for that specific API key. First, try to find this specific email in your email account. It can happen that these e-mails end up in your spam folder. Therefore, make sure your spam folder does not contain this confirmation email. If you cannot find the email containing the API key, please contact us to revoke your API key. You can request a new API key after the old one has been revoked.

What happens when I go over the limits?

You will get back an error response with HTTP code 429.

Can I request a higher rate limit or larger quotas?

In most cases, developers want higher quotas or rate limits because they want to download a (partially) complete dataset. If this is the case, you can take a look at the instructions in the Open Data API documentation .

Why does my API usage not reflect the API calls?

There might be some latency due to updating between your API calls and your API usage.

What if my key no longer works?

Anonymous keys are subject to an expiry date. Read the Open Data API documentation for more information, and to view the latest active keys.

If your personal API key does not work, please contact us.

What are the costs?

All datasets in this portal are free of charge and are provided under the ‘OpenData’ policy of the Dutch government. For more information on the ‘OpenData’ policy, visit the data portal of the Dutch government.

Why are there limits?

To ensure fair usage and to be able to scale operation costs of the KDP, we limit the total number of requests you can make with an API key in a period. Unregistered users that make use of anonymous API keys share these limits among all other active users of that key. To qualify for individual limits, you can register with your personal email address. The limits that apply to your personal API key usage should be suitable for most operational use cases. If you want to download a complete dataset within a reasonable time, take a look at the Open Data API documentation.

What about the protection of my personal data?

Please see our Privacy Statement.

I’m not receiving the latest dataset files for a dataset?

If you view the documentation of the Open Data API in the API Catalog, you can see that the endpoint for listing the dataset files supports the sorting query parameter. This query parameter can be used to determine the sort direction. If set to desc (descending) the endpoint will return all the latest files.

What does X-KNMI-Deprecation in my response mean?

As with any software, features naturally evolve over time. Sometimes a new version for a feature will be substantially different, causing the old version of that feature to be deprecated. This key notifies the end of this feature, API version, or dataset. This key is only present when the feature is announced for deprecation. More information can be found here