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Trace methods

Infura provides access to the following trace API methods to allow users to gain insights into the execution of smart contracts and transactions:


Trace API is currently an open beta feature, available to paying Infura customers.

When tracing transactions, the trace diagnostic options are trace and stateDiff.


trace_block, trace_filter, and trace_transaction returns trace information, whereas trace_call and trace_callMany allow you to use the trace or stateDiff diagnostic options when tracing calls or transactions.


Provides an ordered trace of the instructions executed by the Ethereum Virtual Machine (EVM) during the execution of a smart contract transaction. Excludes precompiled contracts.

Trace example
action Transaction details.
callType Whether the transaction is call or create.
fromAddress of the transaction sender.
gasGas provided by sender.
inputTransaction data.
toTarget of the transaction.
valueValue transferred in the transaction.
resultTransaction result.
gasUsedGas used by the transaction. Includes any refunds of unused gas.
outputReturn value of the contract call. Contains only the actual value sent by a RETURN operation. If a RETURN was not executed, the output is empty bytes.
subTracesTraces of contract calls made by the transaction.
traceAddressTree list address of where the call occurred, address of the parents, and order of the current sub call.
transactionHashHash of the transaction.
transactionPositionTransaction position.
typeWhether the transaction is a CALL or CREATE series operation.


Displays state changes in the requested block for each transaction, represented as a map of accounts to an object. Lists the balance, code, nonce, and storage changes from immediately before the transaction to after the transaction. For the key:value pairs:

  • + indicates the field didn’t exist before and now has the specified value.
  • - indicates a deleted value.
  • * has a from and a to value.

An absent value is distinct from zero when creating accounts or clearing storage. For example, when clearing storage, an absent value means that a particular storage slot has not yet been assigned a value, while a zero value means that the storage slot has been assigned and set to zero.

stateDiff example
balanceChange of balance event
balance.fromBalance before the transaction
balance.toBalance after the transaction
codeChanges to code. None in this example
nonceChange of nonce.
nonce.fromNonce before the transaction.
nonce.toNonce after the transaction.
storageChanges to storage. None in this example.