Web3 & DApp Development Fundamentals · Lesson

Minting and Burning

Supply management.

Minting and Burning is a free Web3 & DApp Development Fundamentals lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Web3 & DApp Development Fundamentals learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.

Managing Supply

Minting creates new tokens and burning destroys them. Together they let a token's totalSupply grow or shrink over time.

These operations are not part of the core ERC-20 interface, but they are extremely common extensions.

What Minting Does

Minting increases totalSupply and credits new tokens to a recipient's balance. It is how tokens enter circulation - at deployment, as rewards, or on demand.

Implementing Mint

A mint function adds to both totalSupply and the recipient's balance, then emits a Transfer event from the zero address.

<code>function _mint(address to, uint256 amount) internal {
    require(to != address(0), 'mint to zero');
    totalSupply += amount;
    balanceOf[to] += amount;
    emit Transfer(address(0), to, amount);
}</code>

Mint Emits From Zero

By convention a mint is logged as a Transfer from address(0). Wallets and indexers interpret a transfer originating at the zero address as new tokens being created.

<code>emit Transfer(address(0), to, amount); // signals minting</code>

What Burning Does

Burning reduces totalSupply and subtracts from a holder's balance, permanently removing tokens from circulation. It is used for deflationary mechanics, redemptions, and buybacks.

Implementing Burn

A burn function checks the holder's balance, decreases it and totalSupply, then emits a Transfer to the zero address.

<code>function _burn(address from, uint256 amount) internal {
    require(balanceOf[from] >= amount, 'burn exceeds balance');
    balanceOf[from] -= amount;
    totalSupply -= amount;
    emit Transfer(from, address(0), amount);
}</code>

Burn Emits To Zero

Symmetrically, a burn is logged as a Transfer to address(0). Tokens sent to the zero address are unrecoverable, which is exactly the intent.

<code>emit Transfer(from, address(0), amount); // signals burning</code>

Access Control on Mint

Minting must be restricted - an open mint function lets anyone create unlimited tokens, destroying value. Gate it behind an owner or minter role.

<code>address public owner;
modifier onlyOwner() { require(msg.sender == owner, 'not owner'); _; }

function mint(address to, uint256 amount) public onlyOwner {
    _mint(to, amount);
}</code>

Burning Your Own Tokens

Holders are usually allowed to burn their own tokens freely. A public burn simply burns from msg.sender.

<code>function burn(uint256 amount) public {
    _burn(msg.sender, amount);
}</code>

Capped Supply

To guarantee scarcity, a token can enforce a maximum supply by checking against a cap before minting.

<code>uint256 public immutable cap;

function mint(address to, uint256 amount) public onlyOwner {
    require(totalSupply + amount <= cap, 'cap exceeded');
    _mint(to, amount);
}</code>

Burn From Allowance

Like transferFrom, a burnFrom lets an approved spender burn another account's tokens, decrementing the allowance first.

<code>function burnFrom(address from, uint256 amount) public {
    require(allowance[from][msg.sender] >= amount, 'allowance');
    allowance[from][msg.sender] -= amount;
    _burn(from, amount);
}</code>

Quick Check

Test your understanding of minting and burning.

Recap

You learned supply management:

Mint increases totalSupply, credits a balance, emits Transfer from address(0)
Burn decreases totalSupply, debits a balance, emits Transfer to address(0)
Minting must be access-controlled; holders can usually burn their own tokens
Caps enforce a maximum supply; burnFrom uses allowances

Frequently asked questions

Is the “Minting and Burning” lesson free?

Yes — the full text of “Minting and Burning” is free to read here on the web, and the Web3 & DApp Development Fundamentals course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Web3 & DApp Development Fundamentals course, upgrade to CoddyKit PRO.

What will I learn in “Minting and Burning”?

Supply management. You practise Web3 & DApp Development Fundamentals with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start Web3 & DApp Development Fundamentals?

No prior experience is required. Web3 & DApp Development Fundamentals on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.

How long does the “Minting and Burning” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this Web3 & DApp Development Fundamentals lesson?

Yes. Every Web3 & DApp Development Fundamentals lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

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