ERC-20 is the Most Widely Used Token Standard on Ethereum. Here's What It Means.

ERC-20 is a technical standard (or token standard) that defines how fungible tokens function in the Ethereum ecosystem

ERC-20 is the most widely used token standard on Ethereum. It provides a simple, consistent set of rules that developers can use to mint and manage fungible tokens – digital assets that each hold the same value and utility.

For example, all ERC-20 tokens have the same functions for checking a user's token balance or transferring tokens between wallets. This standardisation is crucial for the interoperability of different crypto projects and platforms. Without such a standard, the exponential growth of new crypto tokens, wallets, and exchanges would likely have been much more complex and difficult to use.

In this guide, we will detail what ERC-20 means, how it works, why it’s so important, and how it compares with other top Ethereum token standards like ERC-721 and ERC-1155.

What Does ERC-20 Mean?

ERC-20 is a technical standard (or token standard) that defines how fungible tokens function in the Ethereum ecosystem, outlining a set of rules for transferring tokens, checking balances, and approving spending. This standard acts like a “rulebook” for developers, helping them create tokens that are compatible with the rest of the Ethereum ecosystem, such as crypto wallets, decentralized applications (dApps), and exchanges.

It’s important to note that ERC-20 is specific to fungible tokens. This simply means that each token is interchangeable with any other token of the same kind, similar to fiat currencies. For example, one ETH is always interchangeable with any other ETH.

What Is An ERC?

The “ERC” in ERC-20 (and every other Ethereum token standard) stands for Ethereum Request for Comment. ERCs are proposals that suggest some kind of technical improvements or standards for how things should function on the Ethereum network. Because Ethereum is an open-source, decentralized platform with no central authority, the ERC system allows developers to submit ideas to be reviewed and further refined by the broader Ethereum community.

An ERC is created through the following process:

The number “20” in ERC-20 simply identifies this specific proposal. Other major ERCs include ERC-721, the most popular token standard for non-fungible tokens (NFTs), and ERC 1155, a multi-token standard used in many blockchain games that allows both fungible and non-fungible tokens in one contract.

The History of ERC-20

Before ERC-20, each new blockchain-based token had its own custom code, making it difficult for wallets, exchanges, and decentralized applications (dApps) to support them.

ERC-20 was proposed by an Ethereum developer called Fabian Vogelstellar on November 19, 2015. The idea was to create a standard so that all tokens follow the same set of rules, ensuring compatibility across the Ethereum ecosystem. He posted the proposal on GitHub, a platform where developers store and share code. Vogelstellar explained why this process is so important in driving innovation in an interview at Devcon3 if you want to hear more.

The proposal was recognized in late 2017 and formalized in Ethereum Improvement Proposal 20 (EIP-20), which was written by Vogelstellar and Vitalik Buterin, a cofounder of Ethereum, and can be viewed here.

ERC-20 came to the forefront during the 2017/18 initial coin offering (ICO) boom. An ICO is similar to an initial public offering (IPO) but for a new cryptocurrency instead of a stock. Most tokens launched during this period were on the Ethereum network, and ERC-20 became the industry standard. There are now more than 350 thousand ERC-20 assets.

How ERC-20 Tokens Work

ERC-20 tokens serve a wide range of purposes on the Ethereum network. They can represent digital currencies, voting power in governance systems, or even tokenized versions of real-world assets such as real estate or gold. These tokens are powered by smart contracts, which are self-executing lines of code stored on the Ethereum blockchain. These contracts automatically perform specific functions, such as processing transactions, when certain predetermined conditions are met.

When a developer creates an ERC-20 token, they write a smart contract that defines the token’s name, symbol, supply, and how transactions should work. The contract must implement standard ERC-20 functions. For example, balanceOf() allows the user to check their balance while transfer() instructs the contract to send tokens from one wallet to another. Normally, this would require a strong understanding of coding and Solidity, the coding language used on Ethereum, but today, there are platforms that can help you create tokens much more easily.

This standardization has fueled the rapid growth of DeFi by enabling developers to build interoperable wallets, decentralized exchanges, lending apps, and other DeFi platforms without the need for custom coding. As a result, users can easily trade, lend, stake