# finmath Keccak256 Hash

> finmath Keccak256 Hash is a paid API for AI agents from finmath.qzqh5rrbkz.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Computes the Keccak-256 cryptographic hash of an input string, as used in Ethereum and other EVM-compatible blockchains.

## Facts

- Endpoint: POST https://finmath.qzqh5rrbkz.workers.dev/v1/keccak256
- 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/finmath-keccak256-hash-ae210268
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IxnWxbSwiMjm4ewMUYozK

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 finmath-keccak256-hash-ae210268 -d '<json body>'
```

Example prompt: Compute the Keccak-256 hash of the string 'Transfer(address,address,uint256)' so I can get the Ethereum event topic hash.

## When to prefer this

Use this endpoint when you need a deterministic, exact Keccak-256 hash — especially for Ethereum ABI signatures, event topics, or any EVM-compatible hashing — without relying on an LLM's error-prone arithmetic or a local crypto library.

## Known failure modes

- Missing required 'input' field returns validation error
- Invalid encoding value may cause a processing error
- Empty string input may return the keccak256 of empty bytes
- Network timeout from Cloudflare Worker edge

## How this service works

Deterministic finance and crypto math for AI agents: TradFi (NPV, IRR, XIRR, Black-Scholes + Greeks, bonds, VaR, Sharpe) and DeFi (impermanent loss, perp liquidation, funding, Uniswap v3, health factor, cost basis). Exact, model-free arithmetic that LLMs get wrong — priced per call in USDC.

## Output

Returns a JSON object with a 'result' field containing the keccak256 hash (typically as a hex string) of the provided input, along with a 'meta' object with call metadata.

## Example request

```json
{
 "input": "Transfer(address,address,uint256)"
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "string",
   "description": "input"
  },
  "encoding": {
   "type": "string",
   "description": "encoding"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "result",
  "meta"
 ],
 "properties": {
  "meta": {
   "type": "object"
  },
  "result": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/finmath-keccak256-hash-ae210268/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from finmath.qzqh5rrbkz.workers.dev](https://www.zero.xyz/host/finmath.qzqh5rrbkz.workers.dev/llms.txt)