Alchemy Ethereum

Overview

Alchemy is a blockchain developer platform — Ethereum node-as-a-service (plus many other chains) exposing standard JSON-RPC plus enhanced APIs (NFT, Token, Transfers, Alchemy Webhooks). Auth is a free API key (an invalid key returns 401, verified).

Quick Start

JSON-RPC on your network URL (replace YOUR_KEY):

curl "https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc": "2.0", "method": "eth_blockNumber", "params": [], "id": 1}'

{ "jsonrpc": "2.0", "id": 1, "result": "0x12f...e" }

Get a balance:

curl "https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc": "2.0", "method": "eth_getBalance", "params": ["0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae", "latest"], "id": 1}'

Authentication

• Register at alchemy.com → create an app → get the HTTPS URL with your key (/v2/YOUR_KEY).
• The key is embedded in the URL path (an invalid key returns 401 — verified).
• Different chains = different URLs (eth-mainnet, eth-sepolia, polygon-mainnet, …).

Rate Limits & Notes

• Free tier: 300 million compute units/month (300M CU — generous for development); paid plans scale.
• Standard JSON-RPC methods (eth_, net_) work unchanged — drop-in for other node providers.
• Enhanced APIs: NFT API, Token API, Transfers API, Alchemy Webhooks, and Notify.
• Also offers the Alchemy SDK (npm) for convenience.

FAQ

Is Alchemy free? Free tier: 300M compute units/month; more is paid.

How do I get a key? Register at alchemy.com → create an app → the key is in your app’s URL.

Is it standard JSON-RPC? Yes — any eth_* method works as with other Ethereum nodes.