Attestwire API alternatives

Validate EN 16931 e-invoices: XRechnung, ZUGFeRD, Factur-X, Peppol BIS. If it doesn't fit your project, here are the 10 best free Data Validation APIs to use instead in 2026, out of 15 in the directory.

For reference, Attestwire API: Callable from the browser (CORS) · HTTPS.

1
US Autocomplete API
Online · 976 ms
Enter address data quickly with real-time address suggestions.
- Callable from the browser (CORS)
- HTTPS
apiKeyHTTPSCORS
2
US Street Address API
Online · 559 ms
Validate and append data for any US postal address.
- Callable from the browser (CORS)
- HTTPS
apiKeyHTTPSCORS
3T
Temsor API
Online · 668 ms
Validates Turkish national ID, tax number, IBAN, phone, plate and parses addresses.
- Callable from the browser (CORS)
- HTTPS
apiKeyHTTPSCORS
4
US Extract API
Online · 520 ms
Extract postal addresses from any text including emails.
- Callable from the browser (CORS)
- HTTPS
apiKeyHTTPSCORS
5
invowerk API
Online · 727 ms
Validate e-invoices (ZUGFeRD, Factur-X, XRechnung, Peppol BIS) and get a validation report.
- HTTPS
apiKeyHTTPSCORS ?
6
Postman Echo API
Online · 2932 ms
Test api server to receive and return value from HTTP method.
- No API key needed
- HTTPS
No authHTTPSCORS ?
7
VATlayer API
Online · 887 ms
Free and HTTPS secured JSON API offering instant VAT number validation, reliable EU VAT rates and VAT compliant price calculations for developers & businesses.
- HTTPS
apiKeyHTTPSCORS ?
8
RevAddress API
Online · 966 ms
US address standardization, congressional and state legislative districts, Census data; free tier.
- HTTPS
apiKeyHTTPSNo CORS
9
SchemaShield API
Online · 499 ms
Read-only preflight for breaking schema changes and downstream query impact.
- HTTPS
apiKeyHTTPSCORS ?
10
VerifNow API
Online · 487 ms
Validates email, phone, IBAN, EU VAT against VIES, and Canadian, Spanish and US national IDs.
- HTTPS
apiKeyHTTPSNo CORS

Attestwire API vs alternatives

Attestwire API compared with its alternatives
API	API key	HTTPS	CORS	Uptime	Response	Rating
Attestwire	Required	Yes	Yes	Up	700 ms	Not rated
US Autocomplete	Required	Yes	Yes	Up	976 ms	Not rated
US Street Address	Required	Yes	Yes	Up	559 ms	Not rated
Temsor	Required	Yes	Yes	Up	668 ms	Not rated
US Extract	Required	Yes	Yes	Up	520 ms	Not rated
invowerk	Required	Yes	Unknown	Up	727 ms	Not rated
Postman Echo	No	Yes	Unknown	Up	2932 ms	Not rated
VATlayer	Required	Yes	Unknown	Up	887 ms	Not rated
RevAddress	Required	Yes	No	Up	966 ms	Not rated

Head-to-head comparisons

Attestwire API alternatives FAQ

What is the best free alternative to the Attestwire API in 2026?

The top-ranked free alternatives to the Attestwire API are US Autocomplete API, US Street Address API and Temsor API, all in the Data Validation category. Rankings combine access (API key, HTTPS, CORS), daily uptime checks and developer ratings.

Is there a Attestwire API alternative that doesn't need an API key?

Yes: Postman Echo API and PurgoMalum API work without an API key, unlike the Attestwire API, which uses apiKey authentication.

How many Data Validation APIs are similar to the Attestwire API?

The directory lists 15 other free Data Validation APIs. This page compares the top ones side by side.