NumValidate
Data Validation
Open Source phone number validation
No keyHTTPS
invowerk
Validate e-invoices (ZUGFeRD, Factur-X, XRechnung, Peppol BIS) and get a validation report
API key
Required
HTTPS
Supported
Browser calls
Unconfirmed
Status
Not yet checked
How to call it
A starting template for invowerk. Replace ENDPOINT with the path from the official documentation, which we link above rather than guess at.
# Requires an API key. Check the docs for whether it goes in a header or a query parameter.
curl -s "https://invowerk.dev/ENDPOINT" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Accept: application/json"Where this listing comes from
Aggregated from one public source (public-apis), then normalised and checked by us.
Report an issue with this listing ↗Other Data Validation APIs
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Data Validation
Test api server to receive and return value from HTTP method
No keyHTTPS
PurgoMalum
Data Validation
PurgoMalum is a free RESTful web service that filters and removes profanity and unwanted text from input. It supports customization options and can return the results in plain text, XML, or JSON formats.
No keyHTTPS
DataScreenIQ
Data Validation
Screen data for schema drift, type mismatches, and null rate anomalies
API keyCORSHTTPS
RevAddress
Data Validation
US address standardization, congressional and state legislative districts, Census data; free tier
API keyCORSHTTPS
SpryTools Email Validation
Data Validation
Syntax + MX + disposable/role-based email validation
API keyCORSHTTPS
invowerk — common questions
Answered from what our own scheduled checks found, not from the provider's marketing.
Is invowerk free to use?
invowerk is listed in our free catalogue, but it requires an API key, so you will need to register before your first call. Providers frequently reserve higher limits and commercial use for paid plans.
Does invowerk need an API key?
Yes. invowerk authenticates with an API key. Keep it server-side rather than in browser code, because anything in your frontend bundle is readable by anyone who opens developer tools.
Can I call invowerk from browser JavaScript?
We could not confirm CORS support for invowerk. Test it from a browser before relying on it client-side; if the request succeeds in curl but fails in the console, CORS is the reason.
Is invowerk available over HTTPS?
Yes. invowerk serves over HTTPS, so you can call it from a secure page without triggering a mixed-content block.