A South African identity number encodes a birth date, a gender segment, a citizenship digit and a Luhn check digit. verza validates the structure and decodes those fields, returning what the number says and, just as importantly, what it does not prove.
The check is stateless. Identity numbers are never stored and never logged, which is what lets it sit inside a KYC or onboarding flow without becoming a POPIA liability of its own. Structural validity is not registration: a well-formed number that was never issued still passes, and the response says so explicitly.
Structural validation of a South African identity number with safe decode: Luhn check digit, birth date, gender and citizenship segments (citizen or permanent resident). The structural step in KYC, KYB and customer onboarding or due diligence workflows: derive date of birth, age, gender and citizenship without storing the identity. Run it before a paid registry lookup rather than instead of one: a Home Affairs check is priced in rands per query, so screening structurally first means you never spend one on a number that could not have been issued. Stateless, never stored or logged (POPIA-conscious by construction). Confirms structure only, not registration with Home Affairs.
API key. The free tier issues a key at /signup: send it as Authorization: Bearer <key> and calls come off a monthly allowance, no crypto anywhere in that path. Every key comes with a sandbox twin (vz_test_) that never counts against quota and accepts only the documented test inputs, so you can wire up an integration before spending a single call.
Pay per call. Send no key at all and a paid endpoint replies HTTP 402 with the exact payment requirements; an x402 client pays USDC on Base (about two seconds to settle) and retries automatically. No account, no signup, which is what makes it work for autonomous agents.
Either way, invalid input is rejected with a free 400 before any payment is challenged, so you never pay (or spend quota) to learn you made a typo.
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