Hashing, HMAC & Checksum Suite

hash-hmac.underscoredone.com · 1 paid endpoint · listed 2026-10-27

Give this API any text or binary data and it returns its fingerprint under whichever hash algorithms you choose - SHA-256, SHA-512, MD5, BLAKE2, CRC32 and more. It also signs data with a secret key (HMAC) and safely verifies whether an incoming signature matches, using a timing-safe comparison. Language models cannot hash: they emit a string of the right length and character set that is simply wrong, so every webhook check built on a guessed hash is silently broken.

Paid endpoints

Latest checks

Income on Base (7 days)

This provider's payout address is shared by several providers, so its income is not shown as its own.

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<a href="https://logicnodes.io/observatory/p/hash-hmac.underscoredone.com"><img src="https://logicnodes.io/observatory/badge/hash-hmac.underscoredone.com.svg" alt="x402 status"></a>

Claim it for free with x402_provider_claim (sign with your payout address), and get an alert within minutes when it stops answering with x402_monitor_create ($5 for 30 days). Both work over MCP (https://logicnodes.io/mcp/v2) or POST https://logicnodes.io/v1/tools/<tool>.

Income is all USDC received by the provider's payout address on Base, whatever the source. Score: 0-100: 50 x share of checks in the last 72 h that returned valid x402 payment terms + 30 x min(1, log10(1 + USDC received in 7 days) / 4) + 20 x min(1, log10(1 + distinct payers in 7 days) / 3). A provider never checked scores on income only; income is all USDC received by its payout address on Base, whatever the source. JSON: /v1/observatory/providers/hash-hmac.underscoredone.com