Mint Tokens

How to Mint Tokens

Minting tokens refers to the process of creating new units of a token by invoking the mint_to instruction on a token program. Only the address specified as the mint authority on the mint account can mint new tokens. The instruction also requires the existence of a token account for the mint as the destination of the minted tokens.

Examples

To mint tokens through an Anchor program, you need to make a cross program invocation (CPI) to the mint_to instruction on either the Token Program or Token Extension Program.

This means you are invoking the mint_to instruction on the Token Program or Token Extension Program from an instruction in your program. Your program acts as an intermediary, passing along the required accounts, instruction data, and signatures to the token program.

Mint Tokens via CPI

Use the token_interface::mint_to function make a CPI to either the Token Program or Token Extension Program. This function requires:

1. The MintTo struct which specifies the required accounts:

   • mint - The mint account to create new units of tokens for
   • to - The destination token account to receive the minted tokens
   • authority - The mint authority with permission to mint tokens

2. The amount of tokens to mint, in base units of the token adjusted by decimals. (e.g. if the mint has 2 decimals, amount of 100 = 1 token)

The mint authority passed to the mint_to instruction must match the mint_authority stored on the mint account. Additionally, the mint authority must be a signer on the transaction. For example:

use anchor_lang::prelude::*; use anchor_spl::{  token_interface::{self, Mint, MintTo, TokenAccount, TokenInterface}, };   declare_id!("3pX5NKLru1UBDVckynWQxsgnJeUN3N1viy36Gk9TSn8d");   #[program] pub mod token_example {  use super::*;    pub fn mint_tokens(ctx: Context<MintTokens>, amount: u64) -> Result<()> {  let cpi_accounts = MintTo {  mint: ctx.accounts.mint.to_account_info(),  to: ctx.accounts.token_account.to_account_info(),  authority: ctx.accounts.signer.to_account_info(),  };  let cpi_program = ctx.accounts.token_program.to_account_info();  let cpi_context = CpiContext::new(cpi_program, cpi_accounts);  token_interface::mint_to(cpi_context, amount)?;  Ok(())  } }   #[derive(Accounts)] pub struct MintTokens<'info> {  #[account(mut)]  pub signer: Signer<'info>,  #[account(mut)]  pub mint: InterfaceAccount<'info, Mint>,  #[account(mut)]  pub token_account: InterfaceAccount<'info, TokenAccount>,  pub token_program: Interface<'info, TokenInterface>, }

At minimum, the following accounts are required:

#[derive(Accounts)] pub struct MintTokens<'info> {  // The mint authority  #[account(mut)]  pub signer: Signer<'info>,  // The mint account  #[account(mut)]  pub mint: InterfaceAccount<'info, Mint>,  // The destination token account  #[account(mut)]  pub token_account: InterfaceAccount<'info, TokenAccount>,  // The token program  pub token_program: Interface<'info, TokenInterface>, }

Within the instruction logic, use the:

• MintTo struct to specify the required accounts
• token_interface::mint_to function to make the CPI

pub fn mint_tokens(ctx: Context<MintTokens>, amount: u64) -> Result<()> {  // Create the MintTo struct with the accounts required for the CPI  let cpi_accounts = MintTo {  mint: ctx.accounts.mint.to_account_info(),  to: ctx.accounts.token_account.to_account_info(),  authority: ctx.accounts.signer.to_account_info(),  };    // The program being invoked in the CPI  let cpi_program = ctx.accounts.token_program.to_account_info();    // Combine the accounts and program into a "CpiContext"  let cpi_context = CpiContext::new(cpi_program, cpi_accounts);    // Make CPI to mint_to instruction on the token program  token_interface::mint_to(cpi_context, amount)?;  Ok(()) }

Mint Tokens with PDA mint authority via CPI

You can create a mint account with a Program Derived Address (PDA) as the mint authority. This allows your program to programmatically mint tokens by "signing" with the PDA's seeds in the Cross Program Invocation (CPI). This pattern is useful when you want the program itself, rather than an external wallet, to control token minting.

use anchor_lang::prelude::*; use anchor_spl::{  associated_token::AssociatedToken,  token_interface::{self, Mint, MintTo, TokenAccount, TokenInterface}, };   declare_id!("3pX5NKLru1UBDVckynWQxsgnJeUN3N1viy36Gk9TSn8d");   #[program] pub mod token_example {  use super::*;    pub fn create_mint(ctx: Context<CreateMint>) -> Result<()> {  msg!("Created Mint Account: {:?}", ctx.accounts.mint.key());  Ok(())  }    pub fn mint_tokens(ctx: Context<MintTokens>, amount: u64) -> Result<()> {  let signer_seeds: &[&[&[u8]]] = &[&[b"mint", &[ctx.bumps.mint]]];    let cpi_accounts = MintTo {  mint: ctx.accounts.mint.to_account_info(),  to: ctx.accounts.token_account.to_account_info(),  authority: ctx.accounts.mint.to_account_info(),  };  let cpi_program = ctx.accounts.token_program.to_account_info();  let cpi_context = CpiContext::new(cpi_program, cpi_accounts).with_signer(signer_seeds);   token_interface::mint_to(cpi_context, amount)?;  Ok(())  } }   #[derive(Accounts)] pub struct CreateMint<'info> {  #[account(mut)]  pub signer: Signer<'info>,  #[account(  init,  payer = signer,  mint::decimals = 6,  mint::authority = mint,  mint::freeze_authority = mint,  seeds = [b"mint"],  bump  )]  pub mint: InterfaceAccount<'info, Mint>,  pub token_program: Interface<'info, TokenInterface>,  pub system_program: Program<'info, System>, }   #[derive(Accounts)] pub struct MintTokens<'info> {  #[account(mut)]  pub signer: Signer<'info>,  #[account(  init_if_needed,  payer = signer,  associated_token::mint = mint,  associated_token::authority = signer,  associated_token::token_program = token_program,  )]  pub token_account: InterfaceAccount<'info, TokenAccount>,  #[account(  mut,  seeds = [b"mint"],  bump  )]  pub mint: InterfaceAccount<'info, Mint>,  pub token_program: Interface<'info, TokenInterface>,  pub associated_token_program: Program<'info, AssociatedToken>,  pub system_program: Program<'info, System>, }

In this example, mint authority is set to a Program Derived Address (PDA). The PDA is derived using the seed b"mint". This means the program itself controls minting through this PDA.

#[derive(Accounts)] pub struct CreateMint<'info> {  #[account(mut)]  pub signer: Signer<'info>,  #[account(  init,  payer = signer,  mint::decimals = 6,    mint::authority = mint,  mint::freeze_authority = mint,  seeds = [b"mint"],  bump  )]   pub mint: InterfaceAccount<'info, Mint>,  pub token_program: Interface<'info, TokenInterface>,  pub system_program: Program<'info, System>, }

To mint tokens, the program must "sign" with the PDA by including the seeds and bump in the CPI context. This is done by passing the seeds and bump to the with_signer method when creating the CPI context.

pub fn mint_tokens(ctx: Context<MintTokens>, amount: u64) -> Result<()> {    let signer_seeds: &[&[&[u8]]] = &[&[b"mint", &[ctx.bumps.mint]]];    let cpi_accounts = MintTo {  mint: ctx.accounts.mint.to_account_info(),  to: ctx.accounts.token_account.to_account_info(),  authority: ctx.accounts.mint.to_account_info(),  };  let cpi_program = ctx.accounts.token_program.to_account_info();   let cpi_context = CpiContext::new(cpi_program, cpi_accounts).with_signer(signer_seeds);  token_interface::mint_to(cpi_context, amount)?;  Ok(()) }