How check digits work for Latin American IDs (CUIT, CPF, RFC) — and an API that validates 19 of them

Description and use

ValidaLatam API validates 19 Latin American ID types with correct check‑digit algorithms, simplifying data entry.

Problem

Validating Latin American tax and national IDs is hard because each country uses a different check‑digit algorithm and the public specifications are scattered.

Outcome

The API provides deterministic, stateless validation for 19 Latin American ID formats, reducing developer effort and improving data quality.

Workflow

• 1. Identify the ID type (e.g., AR_CUIT).
• 2. Call ValidaLatam endpoint: https://validalatam.ia-latam.app/validate/AR_CUIT?value=20-12345678-6
• 3. Parse JSON response: check "valid", "normalized", and "formatted" fields.
• 4. Store or reject the ID based on the "valid" flag.

Evidence

I packaged all of this as ValidaLatam, a stateless API that validates and formats 19 types: AR_CUIT, AR_CUIL, AR_DNI, AR_CBU, AR_CVU, BR_CPF, BR_CNPJ, MX_RFC, MX_CURP, MX_CLABE, CL_RUT, CO_NIT, PE_RUC, UY_RUT, UY_CI, EC_CEDULA, EC_RUC, PY_RUC and IBAN.

Source

curl "https://validalatam.ia-latam.app/validate/AR_CUIT?value=20-12345678-6"

Source