web3_sha3

web3_sha3 computes the Keccak-256 hash of a single piece of input data and returns it as a 0x-prefixed hex string. It is a pure utility method: it performs no chain lookups, so the result depends only on the bytes you pass in.

Despite the sha3 name, this method returns a Keccak-256 digest, not the finalized NIST SHA-3 standard. The two differ in their padding, so hashing the same input with a generic SHA-3 library produces a different result. This Keccak-256 variant is the one used throughout Ethereum — for function selectors, event topic signatures, storage-slot derivation, and address checksums — which is why this method exists on the JSON-RPC surface.

The input must be a 0x-prefixed hex string. To hash a UTF-8 string, encode it to hex first — for example, "hello world" becomes 0x68656c6c6f20776f726c64.

The params array takes exactly one positional argument.

Response fields

A malformed input (missing 0x prefix or non-hex characters) is rejected with the standard JSON-RPC invalid-params error. See errors.md for the full error envelope and handling guidance.

JavaScript (fetch)

const toHex = (s) =>
  "0x" + [...new TextEncoder().encode(s)]
    .map((b) => b.toString(16).padStart(2, "0"))
    .join("");


const res = await fetch("https://api.triport.io/v1/ethereum", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.TRIPORT_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    jsonrpc: "2.0",
    id: 1,
    method: "web3_sha3",
    params: [toHex("hello world")],
  }),
});


const { result } = await res.json();
console.log("keccak256:", result);

TypeScript SDK (@triport/sdk)

import { Triport } from "@triport/sdk";


const client = new Triport({ apiKey: process.env.TRIPORT_API_KEY! });


const result = await client.ethereum.request<string>("web3_sha3", [
  "0x68656c6c6f20776f726c64",
]);
console.log("keccak256:", result);

Python (triport-sdk)

import os
from triport import Triport


client = Triport(api_key=os.environ["TRIPORT_API_KEY"])


payload = "hello world".encode("utf-8").hex()
result = client.ethereum.request("web3_sha3", ["0x" + payload])
print("keccak256:", result)

• This is Keccak-256, not the finalized SHA-3 standard. If you compute the hash locally to compare, use a Keccak-256 implementation (e.g. ethers' keccak256, or Python's eth-hash/pysha3 Keccak variant), not a generic sha3_256 function.
• The result is always 32 bytes — a 66-character string including the 0x prefix — regardless of input length.
• Passing an empty input ("0x") returns the Keccak-256 hash of the empty byte string: 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470.
• Because the digest is deterministic and computed from your input alone, you can also derive it client-side to avoid a round trip; this method is a convenience for when you want the node to compute it for you.
• Rate limiting is RPS-per-tier with burst; there is no daily quota. A -32003 rate_limited error means you should back off and retry shortly.
• Related: web3_clientVersion — the other method in the web3 namespace.