SaveContract

A CLI tool to download verified smart contract source code from Etherscan and other Etherscan-powered block explorers using the official V2 API.

Features

• Multi-Chain Support: Download contracts from Ethereum, Base, Arbitrum, Polygon, and any other chain supported by the Etherscan V2 API.
• Correct File Structure: Automatically parses the Standard JSON Input format to recreate the correct directory structure and file paths.
• Easy to Use: Simple and intuitive command-line interface.
• Environment Variable Support: Configure your API key once in a .env file.

Installation

You can run savecontract directly using npx without installation.

npx savecontract --address <contract_address> [options]

Or, you can install it globally for easier access:

npm install -g savecontract

Usage

Basic Command

savecontract --address <contract_address> --chainid <chain> --apikey <your_api_key> --output <directory>

Arguments and Options

Long Flag	Short Flag	Description	Default
--address	-a	(Required) The contract address to download.	-
--chainid	-c, -cid	Chain ID or name (e.g., "1", "ethereum", "8453", "base").	"1" (Ethereum)
--output	-o	The output directory for the contract files.	./smartcontracts
--apikey	-k	Your Etherscan API key. Overrides the environment variable.	-
--module	-m	API module to use.	"contract"
--action		API action to use.	"getsourcecode"
--help	-h	Show help.	-
--version	-v	Show version number.	-

API Key Setup

An Etherscan API key (from the free tier) is required. You can provide it in two ways:

1. Via Command Line (highest priority):

   savecontract -a 0x... -k YOUR_API_KEY

2. Via .env file (recommended): Create a .env file in the directory where you are running the command and add your key:

   ETHERSCAN_API_KEY=YOUR_API_KEY
   

Examples

1. Download a contract from Base mainnet:

npx savecontract -a 0x03059433BCdB6144624cC2443159D9445C32b7a8 -c base -o ./base_contracts

(This assumes your API key is in a .env file)

2. Download a contract from Ethereum mainnet (default chain):

npx savecontract -a 0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413

3. Specify API key directly for a contract on Polygon:

npx savecontract --address 0x... --chainid polygon --apikey YOUR_API_KEY

Supported Chains

This tool supports any chain available on the Etherscan V2 API. Use either the chain ID or one of the convenient names below:

Chain Name	Chain ID
Ethereum Mainnet	1
Sepolia Testnet	11155111
Holesky Testnet	17000
Hoodi Testnet	560048
Abstract Mainnet	2741
Abstract Sepolia Testnet	11124
ApeChain Curtis Testnet	33111
ApeChain Mainnet	33139
Arbitrum Nova Mainnet	42170
Arbitrum One Mainnet	42161
Arbitrum Sepolia Testnet	421614
Avalanche C-Chain	43114
Avalanche Fuji Testnet	43113
Base Mainnet	8453
Base Sepolia Testnet	84532
Berachain Mainnet	80094
Berachain Bepolia Testnet	80069
BitTorrent Chain Mainnet	199
BitTorrent Chain Testnet	1028
Blast Mainnet	81457
Blast Sepolia Testnet	168587773
BNB Smart Chain Mainnet	56
BNB Smart Chain Testnet	97
Celo Alfajores Testnet	44787
Celo Mainnet	42220
Cronos Mainnet	25
Fraxtal Mainnet	252
Fraxtal Testnet	2522
Gnosis	100
HyperEVM	999
Linea Mainnet	59144
Linea Sepolia Testnet	59141
Mantle Mainnet	5000
Mantle Sepolia Testnet	5003
Memecore Mainnet	4352
Memecore Testnet	43521
Moonbase Alpha Testnet	1287
Monad Testnet	10143
Moonbeam Mainnet	1284
Moonriver Mainnet	1285
OP Mainnet	10
OP Sepolia Testnet	11155420
Polygon Amoy Testnet	80002
Polygon Mainnet	137
Katana Mainnet	747474
Scroll Mainnet	534352
Scroll Sepolia Testnet	534351
Sonic Blaze Testnet	57054
Sonic Mainnet	146
Sophon Mainnet	50104
Sophon Sepolia Testnet	531050104
Swellchain Mainnet	1923
Swellchain Testnet	1924
Taiko Hekla L2 Testnet	167009
Taiko Mainnet	167000
Unichain Mainnet	130
Unichain Sepolia Testnet	1301
WEMIX3.0 Mainnet	1111
WEMIX3.0 Testnet	1112
World Mainnet	480
World Sepolia Testnet	4801
Xai Mainnet	660279
Xai Sepolia Testnet	37714555429
XDC Apothem Testnet	51
XDC Mainnet	50
zkSync Mainnet	324
zkSync Sepolia Testnet	300
opBNB Mainnet	204
opBNB Testnet	5611

License

MIT