Crypto Newbie / Simulators / Gas Market (EIP-1559)
Ethereum Gas Market (EIP-1559) Simulator
Before EIP-1559 (August 2021), Ethereum gas was a first-price auction — users guessed bids and often overpaid wildly. EIP-1559 introduced base fee + tip: the base fee adjusts algorithmically each block based on demand, and is BURNED (not paid to validators). This simulator runs 15-50 blocks under different demand patterns so you can see how base fee evolves, when tips compete, and how much your transaction actually costs.
Block sequence config
Result over simulated blocks
Final base fee
14.92 gwei
Final cost (your op)
$8.31
Block-by-block
| Block | Base fee (gwei) | Utilization | Median tip | Total (gwei) | Cost (USD) |
|---|---|---|---|---|---|
| #1 | 20.00 | 89% | 0.95 | 20.95 | $11.00 |
| #2 | 19.73 | 91% | 0.95 | 20.69 | $10.86 |
| #3 | 19.51 | 89% | 0.95 | 20.45 | $10.74 |
| #4 | 19.25 | 79% | 0.89 | 20.14 | $10.58 |
| #5 | 18.74 | 91% | 0.96 | 19.70 | $10.34 |
| #6 | 18.54 | 75% | 0.87 | 19.41 | $10.19 |
| #7 | 17.96 | 81% | 0.91 | 18.86 | $9.90 |
| #8 | 17.53 | 96% | 0.98 | 18.51 | $9.72 |
| #9 | 17.45 | 94% | 0.97 | 18.42 | $9.67 |
| #10 | 17.32 | 62% | 0.81 | 18.13 | $9.52 |
| #11 | 16.50 | 70% | 0.85 | 17.35 | $9.11 |
| #12 | 15.87 | 68% | 0.84 | 16.71 | $8.77 |
| #13 | 15.23 | 107% | 2.35 | 17.58 | $9.23 |
| #14 | 15.36 | 77% | 0.89 | 16.25 | $8.53 |
| #15 | 14.92 | 80% | 0.90 | 15.82 | $8.31 |
The base fee adjustment formula
Each Ethereum block targets 50% utilization (15M gas of 30M block limit). When a block exceeds target, the next block's base fee increases by up to 12.5% (proportional to the overshoot). When a block undershoots, base fee decreases by up to 12.5%. This means: sustained high demand can rapidly push base fee from 20 gwei → 200 gwei in ~30 blocks (~6 minutes). But idle blocks rapidly bring it back down. Result: base fee tracks demand smoothly without 100x spikes.
Why base fee is BURNED (not paid to validators)
When EIP-1559 launched, this was the controversial part. Validators previously kept all fees; now they only keep tips. The reasoning: separating base fee from validator payment removes the incentive for validators to manipulate gas (e.g., empty blocks to drive up the next block's price). Burning base fee also creates ETH supply pressure — during high activity, ETH burned exceeds ETH issued, making ETH net DEFLATIONARY. Since merge + EIP-1559, ETH supply has been roughly flat (~120M).
When tips actually matter
Under normal demand, tip ≈ 1-2 gwei is enough — your transaction gets included quickly. Under high demand (NFT mints, popular DEX launches, market crashes), tips spike to 50-200 gwei because users compete to bid into limited block space. The block builder picks transactions by tip-per-gas, so high-tip transactions go first. If you're not in a hurry, set low tip and wait — base fee + your low tip will likely be enough within a few blocks.
Total cost = base fee + tip + gas units
Your total cost = (base_fee_gwei + tip_gwei) × gas_units_used. ETH transfer = 21,000 gas. ERC-20 transfer = ~65k. Uniswap swap = ~150k. NFT mint = ~200k. Aave deposit = ~250k. Complex DeFi tx = 500k+. So if base fee is 30 gwei + 2 gwei tip + ETH at $3500: transfer = (32 × 21000 × 10^-9) × 3500 = $2.35. Uniswap swap = (32 × 150000 × 10^-9) × 3500 = $16.80. NFT mint = $22.40. Complex tx (multi-hop swap + LP deposit) = $55+.
Frequently asked questions
+Why does base fee on the simulator look different from etherscan?
Real-time base fee depends on actual block utilization on mainnet. The simulator uses synthetic patterns (low/normal/high/spike/volatile) to show how the math works. Real mainnet under normal conditions hovers at 10-40 gwei. During spikes (NFT drops, DeFi launches, market crashes) it spikes to 100-500 gwei. The simulator's 'spike-then-fall' pattern mimics this best.
+What's the difference between gas LIMIT and gas USED?
Gas LIMIT is the max you authorize the transaction to consume. Gas USED is what was actually consumed. You're charged for USED, not LIMIT (unless tx reverts — then you pay for the gas spent before revert, but not the unused portion). Always set LIMIT slightly above expected USED (e.g., 200k for a Uniswap swap that uses ~150k) to ensure the transaction has room to complete.
+Can I avoid EIP-1559 fees entirely?
On Ethereum L1, no. But L2 rollups (Arbitrum, Optimism, Base) have their own fee mechanisms — Arbitrum charges L1 publication cost + L2 execution cost, often < $0.10 per swap. Layer 2 is the answer for most users; Ethereum L1 is for high-value transactions where security matters more than cost (institutional flows, settlement-layer ops).
+Why are some blocks fully empty but base fee still falls only 12.5%?
The 12.5% adjustment cap is intentional — it prevents oscillation. If base fee could drop 100% in one empty block then spike 1000% in one full block, the market would be chaotic. The capped adjustment means base fee changes smoothly over multiple blocks, allowing users to react. The trade-off: under extreme idleness (e.g., Christmas Day with no activity), base fee can stay artificially high for many blocks before normalizing.
+What's the difference between EIP-1559 and the proposer-builder split (PBS)?
Different layers. EIP-1559 (2021): fixed the fee market — base fee + tip + burn. PBS / MEV-Boost (2022): separated block construction from block proposing — proposers receive blocks from professional block builders who optimize for MEV extraction. EIP-1559 changed FEES. PBS changed WHO ASSEMBLES BLOCKS. Both still active today.