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Documentation Index

Fetch the complete documentation index at: https://docs.arc.io/llms.txt

Use this file to discover all available pages before exploring further.

Arc denominates all transaction fees in USDC, the native gas token. The fee market uses an EIP-1559 pricing model combined with exponentially weighted moving average (EWMA) smoothing — a technique that calculates the base fee from a weighted running average of recent block utilization, giving more weight to recent blocks and less to older ones. This produces stable, predictable gas costs. For the mechanism design behind these parameters, see Stable fee design.

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Fee parameters

ParameterValueNotes
Gas unitUSDC (18 decimals)Native gas accounting precision
Pricing modelEIP-1559 + EWMA smoothingReplaces per-block recalculation with a moving average
Base fee target~$0.01 per transactionDesign-time target under normal load
Minimum base fee (testnet)20 GweiFloor enforced by the protocol
Maximum base fee1e-3 USDC (~$0.001 per gas unit)Hard ceiling that bounds worst-case cost
Gas throughput20 M gas/secProtocol-level capacity limit
Smoothing methodEWMA of block utilizationShort spikes do not propagate into sudden fee jumps
The EWMA smoothing window calculates each new base fee as a weighted blend of the previous base fee and the latest block’s gas utilization ratio. Because older blocks carry exponentially decreasing weight, short traffic spikes raise the fee only slightly, and the base fee returns to its target quickly once utilization normalizes.
The 18-decimal precision listed above applies to Arc’s native gas accounting. USDC on Arc also provides a standard ERC-20 interface with 6 decimals for application-level transfers and balance display. These are not two separate tokens — they share the same underlying balance. See Contract addresses for the ERC-20 address.

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Submitting transactions

Follow these practices to ensure timely transaction inclusion on Arc.

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Set an adequate max fee

Set maxFeePerGas to at least 20 Gwei. Transactions submitted below this floor may remain pending indefinitely or fail outright. 
import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider("https://rpc.testnet.arc.network");
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);

const tx = await wallet.sendTransaction({
  to: recipient,
  value: ethers.parseUnits("1", 6), // 1 USDC via native send
  maxFeePerGas: ethers.parseUnits("20", "gwei"),
});
Set maxPriorityFeePerGas (the EIP-1559 tip) to incentivize sequencer inclusion. A value of 0 Gwei is accepted, but a small tip (for example, 1 Gwei) can improve inclusion time during high-utilization periods.

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Fetch the current base fee

Query the Arc RPC before submitting to get the latest fee data. Two standard methods are available:
MethodReturnsUse case
eth_gasPriceSuggested gas price as a single valueQuick estimation for simple transactions
eth_feeHistoryBase fee and priority fee history over recent blocksFine-grained estimation when you need historical context
import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider("https://rpc.testnet.arc.network");

// Fetch current gas price
// Returns: hex string (e.g., "0x4a817c800" = 20 Gwei)
const gasPrice: string = await provider.send("eth_gasPrice", []);

// Fetch fee history for the last 5 blocks
// Returns: { baseFeePerGas: string[], gasUsedRatio: number[], reward: string[][] }
const feeHistory = await provider.send("eth_feeHistory", [
  "0x5", // block count
  "latest", // newest block
  [25, 50, 75], // percentiles
]);

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Display fees in USDC

Because Arc denominates gas in USDC, surface fee estimates to users in dollar terms rather than raw Gwei. This avoids confusion and aligns with the stablecoin-native model.

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Common errors

ErrorCauseResolution
transaction underpricedmaxFeePerGas is below the 20 Gwei minimum base fee floorIncrease maxFeePerGas to at least ethers.parseUnits("20", "gwei") and resubmit
intrinsic gas too lowGas limit is lower than the intrinsic cost of the transactionSet the gas limit to at least 21,000 for simple transfers; use eth_estimateGas for contract calls
insufficient funds for gas * price + valueThe sending account’s USDC balance cannot cover both the transfer value and the gas feeFund the account with enough USDC to cover the total cost (value + maxFeePerGas x gasLimit)

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Monitoring

View real-time gas metrics and recent averages using the Arc Gas Tracker. The tracker displays current base fee, historical trends, and per-block utilization.
The parameters on this page reflect the current Arc Testnet configuration. Values such as the minimum base fee, maximum base fee, and throughput limits may change before mainnet launch.