Cronos limits are EVM gas ceilings behind out-of-gas transaction reverts

Set, submit and verify a Cronos gas ceiling

The operating sequence has four stages: select Cronos EVM, simulate the exact call, add measured headroom and inspect the mined receipt.

Start by confirming chain ID 25 for mainnet or 338 for Cronos EVM testnet. Build the final transaction with the same sender, contract address, CRO value and calldata that will be broadcast. Then call eth_estimateGas through MetaMask, ethers or Web3.py. An estimate reproduces the current state path, so changing the amount, recipient, token allowance or contract state invalidates it. Apply a defined buffer to the returned units, submit once and keep the transaction hash. This preparation separates an execution ceiling from the fee quote, which uses a separate field entirely.

After inclusion, open Cronos Explorer or read the receipt through JSON-RPC. Inspect status and gasUsed. Status 1 signals success, while status 0 signals failed top-level execution. Equality between gasUsed and the submitted limit strongly points to out of gas. A smaller count points toward REVERT or another exception. This verification closes the operational loop in Cronos Explorer.

Fee exposure starts with gas units and price

Gas units define execution capacity, while the effective gas price converts consumed units into a CRO fee.

On Cronos EVM, CRO uses 18 decimal places, so one CRO equals 1,000,000,000,000,000,000 base units. One gwei equals 1,000,000,000 of those units. The maximum authorization for a type 2 transaction is gasLimit × maxFeePerGas, while the settled execution charge is gasUsed × effectiveGasPrice. Unused gas units aren't charged. A wallet must still reserve enough CRO for the ceiling before broadcast because EIP-1559 checks fee caps against the sender's balance. The network calculates a base fee for each block and the transaction supplies its priority cap.

A data-free CRO transfer starts at 21,000 gas. At exactly 1 gwei, that count converts to 0.000021 CRO. Multiply this unit rate by the receipt's effectiveGasPrice in gwei to calculate the settled fee. The formula handles a changing network quote while preserving the exact 0.000021 CRO conversion.

What happens when the gas limit is too low?

A gas limit below the executed path makes the top-level transaction halt out of gas and roll back its state changes.

The Ethereum Virtual Machine meters each opcode, memory expansion, storage access, log and nested call. Once the remaining gas reaches zero, execution can't reach later instructions. Cronos records a failed receipt with status 0, removes state writes and discards logs created by the reverted transaction. The sender still pays for the consumed units because validators performed that work. A successful receipt uses status 1.

Out of gas and Solidity's revert don't leave the same gas pattern.

A top-level out-of-gas halt consumes the transaction allowance, so gasUsed normally reaches gasLimit. An uncaught REVERT also produces status 0, yet it returns unused gas after the revert instruction and carries optional reason data. A contract can also contain a failed inner call, inspect its false return value and continue successfully. EIP-150 reserves one sixty-fourth of the parent frame's available gas and forwards at most 63/64 to a child call. That reserve lets the caller handle a failed subcall instead of exhausting the entire parent frame. The receipt then reflects the parent outcome, not every child result.

Rebroadcasting the identical call with more gas fixes allowance exhaustion. If contract conditions trigger REVERT, a larger ceiling funds the same branch and the receipt remains status 0.

Intrinsic gas sets the entry floor

Intrinsic gas is the non-negotiable entry cost deducted before Cronos runs contract bytecode.

A data-free transfer to an existing account starts at 21,000 gas, while a contract-creation transaction starts at 53,000 gas. Those numbers come before dynamic execution. EIP-2028 charges 4 gas for each zero calldata byte and 16 gas for each non-zero byte. EIP-2930 adds 2,400 gas per listed address and 1,900 gas per listed storage key. A node rejects a submitted limit below this calculated floor before normal execution begins, so the transaction doesn't produce the same mined pattern as a contract that exhausts its runtime allowance.

EIP-3860 adds 2 gas per 32-byte word of initcode during creation. Data shape, access lists and deployment code therefore raise the minimum. The four transaction forms below show only the fixed starting count; contract execution adds more.

Which receipt fields confirm an out-of-gas failure?

A Cronos receipt confirms out of gas when status is 0 and gasUsed has reached the submitted gas limit.

Read the transaction object alongside the receipt because the receipt doesn't repeat every submitted field. Compare these four items:

• Transaction gas, which records the authorized ceiling.
• Receipt gasUsed, which records the charged execution units.
• Receipt status, where 1 means success and 0 means failure.
• Receipt logs, which excludes events rolled back with failed top-level execution.

On a Cronos node that exposes debug methods, debug_traceTransaction identifies the terminal frame. An out-of-gas trace stops where an operation lacks enough remaining units. A REVERT trace ends at the explicit instruction and can include return data. If a parent catches a child failure, inspect the nested frames because the top-level receipt can still show status 1. A Geth-style callTracer makes that call boundary visible.

Estimation with MetaMask, ethers and Foundry

Gas estimation should reproduce the exact state-changing path, then add headroom for branch changes before signing.

MetaMask requests an estimate from its connected JSON-RPC provider. ethers exposes estimateGas, Web3.py provides estimate_gas() and Foundry offers cast estimate. Hardhat scripts reach the same RPC method through their provider. Each tool simulates the transaction against a selected block state without committing it, so the sender needs CRO during broadcast rather than simulation.

State-sensitive contracts need repeat estimates. An ERC-20 or CRC20 transfer changes storage balances; an OpenZeppelin allowance path differs between first approval, updated approval and transferFrom. Automated market makers inspect pool reserves, while NFT mints inspect supply and per-address counters. Estimate after the immediately preceding transaction is mined, not before a multi-step batch starts. A 20% buffer is a sensible operating rule for deterministic calls with modest branching. Raise it further only after a trace identifies a legitimate higher-cost path, because an arbitrary ceiling can hide a stale estimate in deployment scripts. Continuous integration should fail whenever a Hardhat fixture crosses that ceiling.

Does a higher gas limit make Cronos execution faster?

A higher gas limit doesn't buy priority; it only permits the EVM to execute more metered work. Type 2 EIP-1559 transactions use two fee-cap fields: maxFeePerGas and maxPriorityFeePerGas. Legacy type 0 transactions use one gasPrice field. Validators order eligible transactions through fee and mempool rules, while gasLimit remains a spending ceiling. Raising 80,000 gas to 120,000 gas won't accelerate a call that consumes 70,000 gas; both settle on the same executed path.

Protocol ceilings beyond the wallet field

Contract deployment faces byte-size ceilings that remain binding even when a wallet supplies ample transaction gas, which is detailed in Using Cronos.

Cronos EVM enforces the EIP-170 runtime code ceiling of 24,576 bytes and the EIP-3860 initcode ceiling of 49,152 bytes. EIP-3860 meters initcode at 2 gas for every 32-byte word, while code deposit costs 200 gas per runtime byte. The EVM call stack stops at depth 1,024. A higher transaction limit can't override these rules. Solidity reports creation bytecode and deployed bytecode separately. Measure both artifacts, then reduce code with the optimizer, linked libraries or separated contracts before Hardhat or Foundry submits the deployment. Deployment sizing belongs in every release build.

Block capacity forms another outer bound. Every block header carries a gasLimit, and one transaction can't reserve more execution than the block accepts. Read the latest block through eth_getBlockByNumber before setting large deployment or migration ceilings because governance and network upgrades can change that value. Cronos EVM doesn't implement EIP-4844 blob execution, so oversized input still travels through ordinary calldata and the EVM ceilings above.

Repeatable maintenance for changing contract paths

Maintenance turns gas limits into a tested release parameter rather than a wallet guess. Record five values for every critical method: estimated gas, configured ceiling, mined gasUsed, receipt status and effectiveGasPrice. Run the suite on Cronos EVM testnet chain ID 338 after Solidity, OpenZeppelin or contract configuration changes. Alert when gasUsed crosses 80% of the configured ceiling, then re-estimate before the next release. Cronos limits stay reliable when identical input fixtures, state setup and receipt checks remain in continuous integration.