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What is a token standard

What is a token standard

A token standard is a set of technical rules that defines how a token behaves on a specific blockchain. It specifies the programming interface -- which functions the token's smart contract must implement, what events it must emit, and how other contracts and applications can interact with it. A token standard is a blueprint for compatibility: any token that follows the same standard can be sent, received, displayed, and traded by any wallet, exchange, or application that supports that standard, without requiring custom integration.

Token standards solve a practical problem. Without them, every project would invent its own token format, and wallets would need custom code to support each one. Standards like ERC-20 (on Ethereum), BEP-20 (on BNB Smart Chain), and SPL (on Solana) provide a common language that the entire ecosystem speaks. When a new project creates a token following ERC-20, it automatically works with every Ethereum wallet, every decentralized exchange, and every portfolio tracker -- from day one.

It is critical to understand what a token standard is and what it is not. A standard describes the technical format of a token: how it can be transferred, how balances are tracked, and how approvals work. It says nothing about the token's purpose, value, or economic role in the project. Two tokens can follow the same standard (ERC-20) while serving completely different functions -- one might be a governance token for a DAO, another might be a utility token for paying AI inference fees. The standard is the container; the token model is the content.

In short: a token standard defines the technical format and interface of a token so that it is compatible with wallets, exchanges, and applications on its blockchain. It describes how the token works mechanically, not what it is for.

How token standards work

The role of smart contracts

On most blockchains, tokens are created by deploying a smart contract -- a program that lives on the chain and executes automatically when called. The token standard defines which functions this smart contract must include. For example, the ERC-20 standard requires the following core functions:

Function Purpose
totalSupply() Returns the total number of tokens in existence
balanceOf(address) Returns the token balance of a specific address
transfer(to, amount) Sends tokens from the caller to another address
approve(spender, amount) Authorizes another address to spend tokens on the caller's behalf
transferFrom(from, to, amount) Sends tokens on behalf of another address (requires prior approval)
allowance(owner, spender) Returns the remaining number of tokens that the spender is allowed to transfer

Any smart contract that implements these functions is ERC-20 compatible. Wallets, exchanges, and decentralized applications check for these functions to determine whether they can interact with the token. This standardization is what allows MetaMask, Uniswap, or any other Ethereum-compatible tool to support thousands of different tokens without needing custom code for each one.

Standards on different blockchains

Each major blockchain has its own token standard or family of standards, reflecting the chain's architecture and programming model:

Standard Blockchain Notes
ERC-20 Ethereum (and EVM-compatible chains) The most widely adopted token standard; the de facto reference for fungible tokens
BEP-20 BNB Smart Chain Functionally identical to ERC-20, adapted for BNB Smart Chain's EVM-compatible environment
SPL Solana Solana's token program; different architecture (account-based rather than contract-based) but serves the same purpose
Native token Various The chain's built-in currency (ETH on Ethereum, SOL on Solana, BTC on Bitcoin); not created by a smart contract but by the protocol itself

EVM-compatible chains (Ethereum, BNB Smart Chain, Polygon, Arbitrum, Base, Avalanche C-Chain) share the ERC-20 interface, which means tokens can often be bridged between these chains with minimal friction. Non-EVM chains like Solana use different standards that achieve the same goals through different technical means.

Fungible vs non-fungible standards

Token standards fall into two main categories:

  • Fungible token standards (ERC-20, BEP-20, SPL) -- each token is identical and interchangeable. One unit of a fungible token is the same as any other unit, just like one dollar bill is interchangeable with another.
  • Non-fungible token standards (ERC-721, ERC-1155) -- each token is unique and represents a distinct item or asset. These are the standards behind NFTs.

In the context of DecAIHub project cards, the Token standard field refers to the fungible token standard used by the project's main token. Most crypto AI projects issue fungible tokens.

Why interoperability matters

The practical value of token standards lies in interoperability -- the ability of different tools and services to work together seamlessly:

  • Wallet support -- a wallet that supports ERC-20 can display and transfer any ERC-20 token without updates. Users do not need a different wallet for each project.
  • Exchange listings -- centralized and decentralized exchanges can list any standard-compliant token through automated processes. Non-standard tokens require custom integration, which creates friction and delays.
  • DeFi composability -- decentralized finance protocols (lending platforms, liquidity pools, yield aggregators) are built to interact with standard tokens. A token that follows ERC-20 can be supplied to a lending pool, used as collateral, or paired in a liquidity pool without any modification.
  • Block explorer compatibility -- explorers like Etherscan automatically recognize and display standard-compliant token transfers, balances, and holder counts.
  • Developer tooling -- standard tokens work out of the box with development frameworks, testing suites, and security audit tools. Non-standard implementations increase audit complexity and the risk of bugs.

What a standard does NOT define

A token standard deliberately leaves many important aspects undefined:

  • Token supply -- the standard does not dictate whether the total supply is fixed, inflationary, or deflationary. These are tokenomics decisions made by the project.
  • Distribution -- how tokens are allocated (team, investors, community, treasury) is not part of the standard.
  • Utility -- the standard does not specify what the token is used for. A token can follow ERC-20 and serve as a governance token, a utility token, a stablecoin, or a meme token.
  • Value -- the standard has no opinion on what the token should be worth. Price is determined by supply, demand, utility, and market dynamics -- none of which are encoded in the standard.

Why it matters for crypto AI projects

For crypto AI projects, token standards affect several practical dimensions:

  • Ecosystem reach -- a project that issues an ERC-20 token on Ethereum can immediately access the largest DeFi ecosystem, the widest wallet support, and the most liquid trading venues. Choosing a less common standard limits the token's immediate reach.
  • Cross-chain deployment -- many AI projects deploy on multiple chains. Understanding token standards helps assess whether a project's multi-chain claims are credible. An ERC-20 token on Ethereum and a BEP-20 token on BNB Smart Chain are functionally equivalent but require separate smart contracts and potentially a bridge for cross-chain transfers.
  • Smart contract risk -- standard-compliant tokens benefit from extensive auditing and community review. Custom or modified token implementations may introduce vulnerabilities that have not been tested by the broader ecosystem.
  • AI-specific token mechanics -- some AI projects add custom logic on top of standard token contracts: dynamic fee mechanisms tied to AI inference usage, staking contracts that require token lock-up before accessing AI services, or reward distribution based on computation contributed. The base token standard provides the foundation; the AI-specific logic is layered on top.

Where this appears in DecAIHub project cards

The Token standard field in a DecAIHub project card records the technical standard of the project's primary token. Common values include:

  • ERC-20 -- the token follows the Ethereum ERC-20 standard (or an EVM-compatible equivalent).
  • BEP-20 -- the token follows the BNB Smart Chain BEP-20 standard.
  • SPL -- the token is an SPL token on Solana.
  • native -- the token is the blockchain's built-in currency, not a smart-contract token.

This field is purely descriptive. It tells you which technical format the token uses and, by extension, which blockchain ecosystem it belongs to. It does not tell you what the token does or how valuable it is.

When reading a project card, the Token standard field is best understood alongside:

  • Main chain -- which blockchain the token is deployed on.
  • Token model -- the economic role the token plays in the project (utility, governance, staking, fee-mechanism, or no token).
  • Token name and ticker -- the human-readable identifiers for the token.

What a token standard alone does not prove

  • A token standard does not prove the token has utility. A project can deploy a perfectly compliant ERC-20 token that serves no purpose within its ecosystem. Technical compliance says nothing about functional necessity.
  • A token standard does not prove security. While standard implementations are well-audited, a project can add custom logic (minting functions, pause mechanisms, admin controls) that introduces vulnerabilities. The standard is a starting point, not a security guarantee.
  • A token standard does not prove the project has AI. Issuing a token on any standard is a purely financial and infrastructure activity. It has no relationship to whether the project has a genuine AI component.
  • A token standard does not prove interoperability beyond its chain. An ERC-20 token on Ethereum is not automatically available on Solana. Cross-chain availability requires bridges, wrapped tokens, or separate deployments -- none of which are part of the standard itself.
  • A token standard does not prove decentralization of the token. A standard-compliant token can have a single owner address with the ability to mint unlimited tokens, freeze transfers, or blacklist addresses. The standard defines the interface, not the access controls.

Do not confuse with

  • Token model -- the token model describes the role of the token (utility, governance, staking, fee-mechanism). The standard describes the format. A token model answers "what is it for?" A standard answers "how does it technically work?"
  • Tokenomics -- tokenomics covers supply, distribution, emission schedule, vesting, and economic incentives. These are economic design decisions, not part of the technical standard.
  • Smart contract -- a token standard is one specific type of smart contract. Not all smart contracts are tokens, and not all tokens are smart contracts (native tokens like ETH or SOL are built into the protocol itself).
  • Protocol -- a blockchain protocol is the full set of rules governing the network. A token standard is a much narrower specification that governs one type of asset on the network.

Frequently asked questions

Are ERC-20 and BEP-20 the same thing?

Functionally, yes. BEP-20 is the BNB Smart Chain equivalent of ERC-20 and uses the same function signatures and interface. The difference is the blockchain they run on: ERC-20 on Ethereum, BEP-20 on BNB Smart Chain. Because BNB Smart Chain is EVM-compatible, the smart contract code is often identical. However, the tokens exist on separate networks and cannot be used interchangeably without a cross-chain bridge.

What happens if a token does not follow a standard?

A non-standard token may not be recognized by wallets, exchanges, or DeFi protocols. Users might not be able to see their balance, transfer tokens, or trade them on decentralized exchanges. Non-standard tokens require custom integration work from every platform that wants to support them, which creates friction and limits adoption. In some cases, non-standard transfer logic has led to tokens getting permanently stuck in smart contracts.

Can a token change its standard?

Not directly. A token's standard is defined by its smart contract, which is immutable once deployed (unless it uses an upgradeable proxy pattern). To "change" standards, a project would typically deploy a new token contract on the target standard and offer a migration or swap mechanism for existing holders. This is uncommon and complex.

Does the token standard affect transaction fees?

Indirectly. The standard defines the smart contract functions that are called during transfers, and different functions consume different amounts of gas (the unit of computation cost on EVM chains). A simple ERC-20 transfer costs roughly 65,000 gas units on Ethereum. Tokens with added logic (such as transfer taxes, reflection mechanisms, or automatic liquidity provision) consume more gas. The standard sets the baseline; custom additions increase the cost.

Why do some projects use native tokens instead of ERC-20?

Native tokens are built into the blockchain protocol itself, not created by a smart contract. They serve as the network's currency for paying transaction fees and, in PoS networks, for staking. Projects that operate their own blockchain (L1 chains or appchains) typically have native tokens because the chain needs a built-in fee currency. Projects deployed as applications on an existing chain typically issue ERC-20 (or equivalent) tokens because they do not control the underlying protocol.

How can I verify which standard a token uses?

On EVM chains, you can check the token's smart contract on a block explorer like Etherscan. If the contract implements the six core ERC-20 functions (totalSupply, balanceOf, transfer, approve, transferFrom, allowance), it is ERC-20 compatible. Most explorers label tokens by their standard automatically. On Solana, the SPL Token Program page on Solscan or Solana Explorer identifies SPL tokens. DecAIHub project cards include the Token standard field to save you this lookup.

External references

See also

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