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📦 Rollups: Scale Ethereum 100x

Learn how Layer 2 rollups bundle transactions for massive scalability

🚀 What are Rollups?

Rollups are Layer 2 scaling solutions that execute transactions off the main blockchain (Layer 1), then bundle hundreds of transactions into a single submission back to L1. This dramatically reduces costs while inheriting Ethereum's security.

⚠️ The Scaling Problem

Ethereum can only process ~15 transactions per second. During high demand, gas prices spike to $50-200+ per transaction. This makes DeFi, NFTs, and gaming prohibitively expensive for average users.

15 TPS
Ethereum Limit
$50-200
Peak Gas Fees
$1M+
Daily Fees Paid

💡 The Rollup Solution

📦

Bundle Transactions

Execute 100s of transactions off-chain, then submit one compressed batch to Ethereum. Shared gas costs across all users.

🔒

Inherit Security

Transaction data is posted to Ethereum, so rollups inherit L1's security. Anyone can verify the state transitions.

💰

Massive Cost Reduction

Fees drop from $50 to $0.10-0.50 per transaction. Makes DeFi accessible to everyone, not just whales.

Faster Finality

Transactions confirm in 1-2 seconds on L2, then get finalized on L1. Much better UX than waiting for L1 blocks.

⚖️ Interactive Comparison

Compare Ethereum mainnet (L1) with rollup performance. Toggle between chains to see the dramatic differences.

Transactions Per Second
15 TPS
Average Gas Price
$50
Transaction Finality
~13 seconds
Security Level
Maximum
✗ Slow and Expensive
Ethereum L1 is secure but expensive. Every transaction competes for limited block space, driving up gas prices during high demand.

🔑 How Rollups Work (Simple Version)

1

Execute Off-Chain

Users submit transactions to the rollup sequencer. Transactions are executed off-chain in a separate environment.

2

Bundle Hundreds Together

The sequencer batches 100-1000s of transactions into a single "rollup block" using data compression.

3

Post to Ethereum

Compressed transaction data is submitted to Ethereum mainnet. One L1 transaction represents hundreds of user transactions.

4

Verify & Finalize

Ethereum verifies the rollup state (via fraud proofs or validity proofs). Once finalized, withdrawals to L1 are enabled.