# Crypto Hash & Selector Calculator (keccak256, sha256, ENS, ABI selector)

> Crypto Hash & Selector Calculator (keccak256, sha256, ENS, ABI selector) is a paid API for AI agents from webtools402.176-109-107-191.sslip.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Computes keccak256, sha256, 4-byte ABI function selectors, event topic0 hashes, ENS namehash, or ENS labelhash from a string or hex input.

## Facts

- Endpoint: GET https://webtools402.176-109-107-191.sslip.io/crypto/hash
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crypto-hash-selector-calculator-keccak256-sha256-ens-abi-selector-90c2e03b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tpO-_xkXMsx_cMOGTF5N4

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability crypto-hash-selector-calculator-keccak256-sha256-ens-abi-selector-90c2e03b
```

Example prompt: What's the keccak256 hash of the UTF-8 string 'Hello, World!' and also give me the 4-byte ABI function selector for transfer(address,uint256)?

## When to prefer this

Use this endpoint when an AI agent needs to compute blockchain-relevant hashes on demand — especially Ethereum ABI function selectors, event topic0 values, ENS namehash/labelhash, or general-purpose keccak256/sha256 digests — without running local crypto libraries. Ideal for Solidity development tooling, ENS resolution workflows, or verifying ABI encoding.

## Known failure modes

- Missing required 'algo' or 'input' query params returns 400
- Invalid algorithm name not in enum returns 400
- Hex input that is not valid hex returns 400 or parse error
- Malformed ENS name for namehash/labelhash may return an error
- Payment not provided or insufficient returns 402

## How this service works

Compute keccak256/sha256, a 4-byte function selector, an event topic0, or an ENS namehash/labelhash from a string or hex input.

## Output

Returns the computed hash or selector as a hex string. For keccak256/sha256: a 32-byte hex digest. For selector: a 4-byte hex value. For event_topic: a 32-byte topic0. For namehash/labelhash: a 32-byte ENS-standard hash. Response is a JSON object with the result field.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "algo",
      "input"
     ],
     "properties": {
      "algo": {
       "enum": [
        "keccak256",
        "sha256",
        "selector",
        "event_topic",
        "namehash",
        "labelhash"
       ],
       "type": "string"
      },
      "input": {
       "type": "string",
       "description": "String / signature / ENS name / 0x-hex"
      },
      "encoding": {
       "enum": [
        "utf8",
        "hex"
       ],
       "type": "string",
       "description": "How to read `input` for keccak256/sha256 (default utf8)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crypto-hash-selector-calculator-keccak256-sha256-ens-abi-selector-90c2e03b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from webtools402.176-109-107-191.sslip.io](https://www.zero.xyz/host/webtools402.176-109-107-191.sslip.io/llms.txt)