Kaia vs. Ethereum: A Comparison for Builders

This comprehensive comparison reveals the key differences and similarities between Kaia blockchain and Ethereum, providing developers and users with the essential information needed to understand migration requirements and opportunities.

Overview

Ethereum	Kaia
Established Layer 1, large ecosystem & community	EVM-compatible Layer 1, formed from the Klaytn & Finschia merger. Focus on Web3 adoption in Asia, enterprise-grade reliability, high performance.

User Perspective

Feature	Ethereum	Kaia
Transactions Per Second (TPS)	~15-30 TPS (can vary)	Up to 4,000 TPS. Real-time TPS reported as significantly higher than Ethereum.
Block Time	~12 seconds.	1-second block generation time.
Finality	~13-15 minutes (2 epochs)	Immediate finality (PBFT-based consensus).
Transaction Fees (Gas)	Variable, EIP-1559 auction model	EIP-1559 compatible dynamic fee model with fee delegation allowing applications to pay user fees.
Wallet Compatibility	MetaMask, Ledger, Trust Wallet, etc.	Compatible with Ethereum wallets (for example, MetaMask via RPC config). Kaia-specific wallets (for example, Kaia Wallet).
Token	ETH	KAIA

Developer Perspective

Feature	Ethereum	Kaia
Virtual Machine	Ethereum Virtual Machine (EVM)	EVM-compatible (Kaia Virtual Machine - KVM, based on EVM) and continually updated to support the latest Ethereum opcodes, so Solidity contracts run without modification.
Smart Contract Languages	Solidity, Vyper, Yul, etc.	Solidity, Vyper, Yul, Huff.
Precompiles	Standard Ethereum precompiles	Supports standard EVM opcodes and additional Kaia-specific precompiled contracts.
Development Tools	Smart Contracts Development Tools: Remix, Hardhat, Foundry, etc. Web3 libraries: Ethers, Web3js, Web3j, Web3py, Viem	Smart Contracts Development Tools: Compatible with Ethereum tools (Remix, Hardhat, Foundry, etc.) Web3 libraries: Compatible with Ethers, Web3js, Web3j, Web3py, Viem. Kaia provides its own SDK extensions.
Transaction Types	Legacy, EIP-2930, EIP-1559, EIP-4844, etc.	Supports major Ethereum transaction types (Legacy, EIP-2930, EIP-1559), plus native transaction types like fee delegation and partial fee delegation.
Gas Mechanism	EIP-1559 (base fee + priority fee auction)	EIP-1559 compatible dynamic gas fee model with Gas Abstraction for token-based fee payments and EIP-7623 compatible calldata pricing for seamless SDK compatibility.
Account Model	Externally Owned Accounts (EOAs), Contracts	Supports standard Ethereum accounts and EIP-7702 that allows EOAs to have smart contract code. Features native account abstraction with capabilities like flexible key management.
RPC API	Standard Ethereum JSON-RPC API (eth_ namespace)	Largely compatible. Provides eth_ namespace for Ethereum compatibility. kaia_ namespace for Kaia-specific features.
Websockets	Supported	Supported
Consensus	Proof-of-Stake (Gasper: Casper-FFG + LMD-GHOST)	Optimized version of Istanbul BFT (IBFT), a PBFT-variant. Uses Verifiable Random Function (VRF) for proposer selection.
Node Architecture	Execution clients, Consensus clients	Multi-layered: Core Cells (CCs) with Consensus Nodes (CNs) and Proxy Nodes (PNs); Endpoint Nodes (ENs); Service Chain Nodes.
Governance	Primarily off-chain, community-driven.	On-chain governance involves a Governance Council (GC) composed of reputable organizations. Voting rights proportional to staked KAIA.

What Stays the Same

• High EVM compatibility: Kaia's strong EVM compatibility means most Ethereum dApps, tools (Hardhat, Foundry, Remix), and Solidity contracts can be migrated or used with minimal changes. This is the biggest "stays the same" aspect.
• Familiar Development Tools & Languages: Solidity remains the primary smart contract language. Ethereum development tools like Remix, Hardhat, and Foundry are largely usable.
• Standard Ethereum Wallet Compatibility: Standard Ethereum wallets like MetaMask can be used by changing the RPC URL and ChainID.
• eth_ RPC Namespace: The eth_ namespace for RPC APIs allows interaction similar to Ethereum for common functionalities, ensuring compatibility with existing Ethereum tools for standard operations.
• Standard Ethereum Address Format: Kaia uses the standard Ethereum address format (0x + 40 hex chars).

What’s Different

• Performance & Cost:
  • Expect significantly higher Transactions Per Second (TPS) (up to 4,000 TPS) compared to Ethereum's ~15-30 TPS.
  • Block times are much faster at 1-second.
  • Kaia offers immediate finality, a significant difference from Ethereum's probabilistic finality.
  • Transaction fees (gas) are designed to be low and stable, using an EIP-1559 compatible fee model. Gas price will be in kei.
• RPC & SDKs:
  • While eth_ namespace is supported, the kaia_ namespace is necessary for new or Kaia-specific features and transaction types.
  • Legacy klay_ namespace might exist and is equivalent to the kaia_ namespace.
  • Kaia provides its own SDK extensions for popular Web3 libraries (Ethers-ext, Web3js-ext, Web3j-ext, Web3py-ext, and Viem-ext) that enable seamless migration from Ethereum while providing access to Kaia's enhanced features and performance benefits.
• Native Features (Beyond Standard EVM):
  • Account Abstraction: Kaia has advanced account features (for example, multiple keys per account, role-based permissions), offering more flexibility than Ethereum's EOA model.
  • Transaction Types: Kaia will have its own native transaction types alongside Ethereum's (for example, for account updates, fee delegation). For Ethereum transactions, use standard eth_ RPCs for best compatibility.
  • Fee Delegation: This feature can significantly improve UX by allowing dApps to pay gas fees for users.
• Consensus & Governance:
  • The consensus mechanism is an optimized version of Istanbul BFT (IBFT), different from Ethereum's Gasper, leading to faster block times and immediate finality.
  • Governance involves an on-chain Governance Council (GC), differing from Ethereum's more fluid off-chain governance.
• Token: The native token is KAIA. Tokenomics and utility is specific to Kaia.
• Node Architecture: Kaia uses a purpose-built, layered architecture with specialized node types (Core Cells for consensus, Endpoint Nodes for public access) designed to optimize performance and security, differing from Ethereum's unified client approach.
• Mempool: Transaction handling and public mempool visibility might differ due to Kaia's specific network architecture, with less emphasis on a global, public mempool like Ethereum's.
• Precompiled Contracts: While base EVM precompiles are supported, Kaia may feature additional Kaia-specific precompiled contracts.

Next Steps for Builders

1. Configure Your Environment
   Configure your existing Ethereum tools to work with Kaia:

• Mainnet RPC: https://public-en.node.kaia.io (Chain ID: 8217)
• Testnet: Kairos testnet for testing (get free tokens from faucet)
• Tools: Hardhat, Foundry, and MetaMask work without modification

2. Deploy and Test
   Your Solidity contracts deploy unchanged due to full EVM compatibility. Test on Kairos testnet to verify gas usage patterns under Kaia's dynamic fee model.

3. Leverage Kaia's Advantages

• Immediate Finality: 1-second blocks with instant finality eliminate confirmation waiting
• Lower Gas Costs: Build features that would be too expensive on Ethereum
• Fee Delegation: Let your dApp pay user transaction fees to improve UX
• Gas Abstraction: Users can pay fees with approved tokens (not just KAIA)

4. Use Appropriate APIs and SDKs

• Standard eth_ namespace for Ethereum-compatible operations
• kaia_ namespace for accessing Kaia-specific features and transaction types
• While ethers.js and web3.js work perfectly, consider exploring Kaia's SDKs for easier integration with native features.

5. Stay Informed

• Consult the Kaia Docs that are your primary source for the latest information.
• Engage with other builders and the Kaia team on the Kaia Developer Forum and other community channels for support and updates.