Explore free Data Validation APIs available for developers. Browse our collection of public APIs in the Data Validation category, each verified and documented for easy integration into your projects.
Last verified: November 12, 2026
| Name | Description | Auth | HTTPS | CORS | Uptime (30 days) |
|---|---|---|---|---|---|
| API Adresse | Official French address validation service | none | Yes | unknown | 100% (5 checks) |
| Attestwire | Validate EN 16931 e-invoices: XRechnung, ZUGFeRD, Factur-X, Peppol BIS | apikey | Yes | yes | 100% (5 checks) |
| invowerk | Validate e-invoices (ZUGFeRD, Factur-X, XRechnung, Peppol BIS) and get a validation report | apikey | Yes | unknown | 100% (5 checks) |
| Nonprofit Check Plus | Verify charities via EIN using IRS, PUB78, BMF & OFAC data for compliance and legitimacy | apikey | Yes | unknown | 100% (5 checks) |
| Postman Echo | Test api server to receive and return value from HTTP method | none | Yes | unknown | 100% (5 checks) |
| RevAddress | US address standardization, congressional and state legislative districts, Census data; free tier | apikey | Yes | no | 100% (5 checks) |
| SchemaShield | Read-only preflight for breaking schema changes and downstream query impact | apikey | Yes | unknown | 100% (5 checks) |
| sthan.io Address Autocomplete | Real-time US address suggestions as users type | apikey | Yes | no | 100% (5 checks) |
| sthan.io Address Parser | Parse freeform US addresses into structured fields (house number, street, unit, city, state, ZIP) | apikey | Yes | no | 100% (5 checks) |
| sthan.io Address Verification | Validate and standardize US addresses, with ZIP+4 and deliverability status | apikey | Yes | no | 100% (5 checks) |
| Temsor | Validates Turkish national ID, tax number, IBAN, phone, plate and parses addresses | apikey | Yes | yes | 100% (5 checks) |
| US Autocomplete | Enter address data quickly with real-time address suggestions | apikey | Yes | yes | 100% (5 checks) |
| US Extract | Extract postal addresses from any text including emails | apikey | Yes | yes | 100% (5 checks) |
| US Street Address | Validate and append data for any US postal address | apikey | Yes | yes | 100% (5 checks) |
| Validate UK Postcodes | This API validates postal codes within UK | apikey | Yes | yes | 100% (5 checks) |
| VatcheckAPI | VAT Number Validation & Lookup REST API | apikey | Yes | yes | 100% (5 checks) |
| vatlayer | VAT number validation | apikey | Yes | unknown | 100% (5 checks) |
| VerifNow | Validates email, phone, IBAN, EU VAT against VIES, and Canadian, Spanish and US national IDs | apikey | Yes | no | 100% (5 checks) |
| VerifyEd | Verify academic credentials — search 912K+ schools, detect diploma mills worldwide | apikey | Yes | yes | 100% (5 checks) |
| Veriport | EU VAT validation (VIES), VAT rates, IBAN validation, French company data | apikey | Yes | yes | 100% (4 checks) |
| WISEPIM | Free keyless API: GTIN/EAN/UPC validation with GS1 prefix country, HS code search and EU/US tariff lookup, and EU marketplace fees | none | Yes | yes | 100% (4 checks) |
3 of these APIs require no authentication — you can start making requests immediately without signing up for an account. Just pick one from the table above, check its documentation, and send your first request.
18 APIs in this category require a free API key. This usually means creating a free account on the provider's website and copying your key from the dashboard. The process typically takes less than a minute.
Not sure where to start? Check the uptime column: it shows how often each API's documentation responded to our daily checks over the last 30 days, and the dot shows whether it responded at the latest check. For browser-based projects, check that the API supports CORS.
Yes, all APIs listed on API Bouncer have a free tier. Some are completely open (no sign-up needed), while others require a free account to get an API key. Free tiers typically have rate limits — check each API's documentation for specifics.
It depends on your needs. Consider: Do you need authentication or prefer no-auth? Does your project need CORS support for browser access? How many requests will you make? Start with a no-auth API to prototype quickly, then switch to a more feature-rich option if needed.
We run periodic health checks on all listed APIs. The "Status" column shows whether each API was responding at our last check. APIs marked as "alive" were recently verified. You can also test any API yourself using curl or our guides on testing APIs.
Most free APIs allow commercial use, but terms vary by provider. Always check the specific API's terms of service. Some APIs have separate free and commercial tiers with different rate limits.
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