What Does ERC-20 Stand For, and Why the Number 20?
Breaking down the name
ERC stands for Ethereum Request for Comments. The "Request for Comments" phrasing is borrowed from a long-running tradition in internet standards, where technical proposals are published openly so anyone can review and comment on them. Ethereum adopted the same spirit: improvements to the ecosystem are written up as public proposals, discussed, and — if accepted — become standards.
20 is simply the proposal's serial number. The token standard happened to be proposal number twenty in that process, which is why its formal home is EIP-20 (Ethereum Improvement Proposal 20). The number says nothing about the tokens themselves — it's a filing number, like a bill number in a legislature.
So "an ERC-20 token" just means: a token whose contract follows the rules laid out in Ethereum proposal number 20. If you want the fuller picture of what such a token is and how it differs from Ether, see what an ERC-20 token is.
Is "ERC-20" a ticker symbol?
No — and this trips people up, because exchange screens sometimes display "ERC-20" so prominently that it looks like a coin's name. ERC-20 is the category, not a currency. Each individual token has its own name and its own ticker symbol. In fact, the standard itself defines optional `name` and `symbol` functions that a token contract can implement, which is how wallets and block explorers know what label to show you for a given token.
What the standard actually specifies
The ERC-20 standard is short. It defines a common interface — a fixed set of functions and events — that a token contract must expose:
- totalSupply — how many units of the token exist
- balanceOf — how many units a given address holds
- transfer and transferFrom — moving tokens between addresses
- approve and allowance — letting another address (often an app) spend tokens on your behalf, up to a limit
- Transfer and Approval events — the log entries that wallets and explorers read to show you activity
It also defines the optional `name`, `symbol`, and `decimals` functions that control how a token is displayed.
Why a numbered standard matters
Before a shared standard, every token contract could work differently, and every wallet or exchange would need custom code for each one. With a common interface, supporting one ERC-20 token means supporting essentially all of them — which is a big part of why tokens on Ethereum spread so quickly.
ERC-20 is not the only numbered standard, either. Other proposals define other token types — for example, the standards behind non-fungible tokens (NFTs), where each token is unique rather than interchangeable. When you see "ERC" followed by a different number, it's the same proposal process, just a different rulebook.
The takeaway
- ERC-20 = Ethereum Request for Comments, proposal 20 — a public standard, not a coin or a network.
- The "20" is a filing number with no deeper meaning.
- Individual tokens carry their own names and symbols; ERC-20 is the format they share.