Flow Playground

Initialize Flow Configuration

How to initialize Flow configuration using CLI

Flow CLI uses a state to operate which is called configuration (usually flow.json file). Before using commands that require this configuration we must initialize the project by using the init command. Read more about state configuration here.

flow init

Example Usage

> flow init

Configuration initialized
Service account: 0xf8d6e0586b0a20c7

Start emulator by running: 'flow emulator' 
Reset configuration using: 'flow init --reset'

Error Handling

Existing configuration will cause the error bellow. You should initialize in an empty folder or reset configuration using --reset flag or by removing the configuration file first.

❌ Command Error: configuration already exists at: flow.json, if you want to reset configuration use the reset flag

Global Configuration

Flow supports global configuration which is a flow.json file saved in your home directory and loaded as the first configuration file wherever you execute the CLI command.

Please be aware that global configuration has the lowest priority and is overwritten by any other configuration file if they exist (if flow.json exist in your current directory it will overwrite properties in global configuration, but only those which overlap).

You can generate a global configuration using --global flag.

Command example: flow init --global.

Global flow configuration is saved as:

  • MacOs: ~/flow.json
  • Linux: ~/flow.json
  • Windows: C:\Users\$USER\flow.json



  • Flag: --reset

Using this flag will reset the existing configuration and create a new one.


  • Flag: --global

Using this flag will create a global Flow configuration.

Service Private Key

  • Flag: --service-private-key
  • Valid inputs: a hex-encoded private key in raw form.

Private key used on the default service account.

Service Key Signature Algorithm

  • Flag: --service-sig-algo
  • Valid inputs: "ECDSA_P256", "ECDSA_secp256k1"
  • Default: "ECDSA_P256"

Specify the ECDSA signature algorithm for the provided public key.

Flow supports the secp256k1 and P-256 curves.

Service Key Hash Algorithm

  • Flag: --service-hash-algo
  • Valid inputs: "SHA2_256", "SHA3_256"
  • Default: "SHA3_256"

Specify the hashing algorithm that will be paired with the public key upon account creation.


  • Flag: --log
  • Short Flag: -l
  • Valid inputs: none, error, debug
  • Default: info

Specify the log level. Control how much output you want to see while command execution.