Attestwire API vs Postman Echo API

Two free Data Validation APIs compared on access, reliability and developer ratings, using data from our daily health checks.

The verdict

Choose Attestwire API if you want to call it from browser JavaScript, faster responses.
Choose Postman Echo API if you want to start without an API key.

	Attestwire API	Postman Echo API
What it does	Validate EN 16931 e-invoices: XRechnung, ZUGFeRD, Factur-X, Peppol BIS.	Test api server to receive and return value from HTTP method.
Provider	Attestwire	Postman
API key	Required	Not needed
HTTPS	Yes	Yes
CORS (browser calls)	Yes	Unknown
Status today	Online · 700 ms	Online · 2932 ms
Uptime (30 days)	Up	Up
Developer rating	Not rated yet	Not rated yet
Price	Free / free tier	Free / free tier

Validate EN 16931 e-invoices: XRechnung, ZUGFeRD, Factur-X, Peppol BIS.

EN 16931 validation and generation over HTTP. Errors that teach the regulation.

Strengths

Test api server to receive and return value from HTTP method.

Strengths

Prototyping or a tutorial? Pick the one that needs no API key.
Calling from a web page? You need CORS. Otherwise route requests through your own server or a serverless function.
Going to production? Favour HTTPS, a strong uptime record and a provider with clear rate limits and terms. Check each API's docs before you commit.
Still unsure? Both are free to try: send one request to each and compare the data you get back.

Attestwire API requires an API key; Postman Echo API doesn't, so Postman Echo API is quicker to try.

Attestwire API supports CORS, so front-end JavaScript can call it directly. Call the other from a server.