Updated Mar 27, 2026
Blockchain Reference Hub
Block times, finality, TPS, consensus mechanisms, and EVM compatibility — across the major chains.
Statistics are approximate and subject to change with protocol upgrades. Last reviewed: March 2026.
Chain Overview
First blockchain; most decentralized; energy-intensive.
Smart contract hub; DeFi foundation; EVM standard.
Highest throughput L1; low fees; periodic outage history.
Ethereum sidechain; low fees; gaming and NFT ecosystem.
Sub-second finality; subnet architecture for custom chains.
Largest Ethereum L2 by TVL; EVM-equivalent.
Side-by-Side Comparison
| Chain | Consensus | Block Time | Finality | TPS (real) | Fees | EVM |
|---|---|---|---|---|---|---|
| Bitcoin | Proof of Work (SHA-256) | ~10 min | ~60 min (6 conf.) | ~7 | $1–$5 typical | ✗ |
| Ethereum | Proof of Stake (post-Merge) | ~12 sec | ~15 min (2 epochs) | ~15–30 | $5–$50+ typical | ✓ |
| Solana | Proof of History + PoS | ~400 ms | ~13 sec | ~2,000–4,000 | < $0.01 typical | ✗ |
| Polygon PoS | Proof of Stake | ~2 sec | ~5 min (ETH checkpoint) | ~7,000 | < $0.01 typical | ✓ |
| Avalanche | Snowball (DAG-based BFT) | ~2 sec | ~1–2 sec | ~4,500 | < $0.10 typical | ✓ |
| Arbitrum | Optimistic Rollup (ETH L2) | ~250 ms | ~7 days / ~15 min (fast bridge) | ~40,000 theoretical | < $0.10 typical | ✓ |
Statistics are approximate. Fees vary significantly based on network congestion. TPS figures reflect real-world sustained throughput, not theoretical maximums.
Consensus Mechanisms
Finality Explained
Finality is the point at which a transaction is considered irreversible. It varies significantly across chains.
Probabilistic
Never truly final — just increasingly unlikely to reverse. Each additional block makes a reorg exponentially more expensive. Bitcoin uses 6 confirmations (~60 min) by convention.
Economic
Reversion is cryptographically possible but economically irrational. Slashing penalizes validators for double-signing. After finalization, reverting would require burning billions in staked ETH.
Deterministic
Truly irreversible once consensus is reached. No probabilistic uncertainty. Avalanche achieves this via Snowball BFT — once a supermajority agrees, the decision is permanent.
| Chain | Finality Type | Time | Notes |
|---|---|---|---|
| Bitcoin | Probabilistic | ~60 min | 6 confirmations convention |
| Ethereum | Economic | ~15 min | 2 epochs; slashing enforces |
| Solana | Economic | ~13 sec | PoS-based validator consensus |
| Polygon PoS | Economic | ~5 min | Checkpointed to Ethereum |
| Avalanche | Deterministic | ~1–2 sec | Snowball BFT consensus |
| Arbitrum | Optimistic Rollup | 7 days / 15 min | Challenge period / fast bridge |
Layer 1 vs Layer 2
Layer 1 — Base Chain
The root blockchain. Sets consensus rules, validates all transactions natively, and provides the highest security guarantee. Usually slower and more expensive due to decentralization constraints.
Examples: Bitcoin, Ethereum, Solana, Avalanche
Layer 2 — Scaling Solution
Built on top of an L1 to scale throughput and reduce fees. For rollups, security is inherited from the L1 — the L2 posts compressed transaction data back to Ethereum.
Examples: Arbitrum, Optimism, Base, zkSync, Lightning Network
Types of Layer 2
Optimistic Rollups
Assume validity; 7-day fraud proof window. Examples: Arbitrum, Optimism, Base.
ZK Rollups
Cryptographic validity proofs; instant finality on L1. Examples: zkSync, Starknet, Polygon zkEVM.
State Channels
Off-chain payment channels; only open/close on-chain. Example: Lightning Network (Bitcoin).
Sidechains
Independent chains with own consensus; bridge to L1. Example: Polygon PoS (uses checkpointing).
Why it matters: Ethereum mainnet fees can reach $5–$50 per transaction during congestion. L2s bring this to cents while inheriting Ethereum's security.
EVM Compatibility
EVM-compatible chains run the same Solidity smart contracts, work with MetaMask, and use the same developer tooling as Ethereum. Non-EVM chains use entirely different programming models.
| Chain | EVM | Notes |
|---|---|---|
| Ethereum | ✓ Yes | Origin of EVM; reference implementation |
| Arbitrum | ✓ Yes | EVM-equivalent; same tooling as Ethereum |
| Optimism | ✓ Yes | EVM-equivalent; OP Stack |
| Base | ✓ Yes | Built on OP Stack; Coinbase-operated |
| Polygon PoS | ✓ Yes | EVM-compatible; uses same Solidity contracts |
| Avalanche C-Chain | ✓ Yes | EVM-compatible; Avalanche's contract chain |
| BNB Chain | ✓ Yes | EVM-compatible; Binance Smart Chain |
| Bitcoin | ✗ No | Script-based; no general smart contracts |
| Solana | ✗ No | Rust-based programs; not EVM-compatible |
| Cardano | ✗ No | Plutus (Haskell-based); not EVM |
| Near | ✗ No | Rust/AssemblyScript; NEAR runtime |