HOTP (counter-based)
Generate an RFC 4226 counter-based HMAC one-time password from a base32 secret and counter. Configurable digits (6–10, default 6) and algorithm (SHA1/SHA256/SHA512, default SHA1). An invalid base32 secret is a clean 400.
Go to this service →Our latest check (2026-10-11)
- Answering
- Yes — valid x402 payment terms
- Time to answer
- 386 ms
- Price
- $0.004 per call
- Paying buyers, last 30 days
- 1 (directory's own records)
- Paid calls, last 30 days
- 1
- Category
- Unclassified
- Address
- https://otp.openverbs.com/v1/hotp
Accuracy: paid answers checked against an independent record
Not yet in our paid checks. A seller we have not checked has neither passed nor failed.
For agents
This page as JSON: /sellers/10ad8890dc73.json. Paid lookup by address: GET /api/seller?resource=… ($0.001, x402).