Transactions API

What gas limit does this transaction need?

The gas limit to sign an unsigned EVM transaction with, estimated against the latest state, or why it would revert or cannot be paid for.

POST/api/external/transaction-analysis/gas-limit-estimate/{chain}

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What it returns

Asks the chain for the gas limit to sign an unsigned transaction with, run against the latest state. Answers the limit when the transaction would succeed; otherwise whether it would revert, with the revert reason, or could not run because the sender cannot pay the value sent plus gas. The limit is the chain's own estimate, usually above the gas the run uses, and holds only for the state it ran against: the next block can change it. No signature, nonce or fee is checked.

Chains

BNB Chain BNB
Ethereum ETH
Stable STABLE
Base BASE
Robinhood Chain RHC
Arc ARC

Request

Send your key in the x-dex-data-key header. Replace each <placeholder> with a real value.

curl -X POST -H "x-dex-data-key: $DEXDATA_API_KEY" \
  -H "content-type: application/json" \
  -d '{"from":"<from>","to":"<to>","data":"<data>","value":"<value>"}' \
  "https://api.dexdata.io/api/external/transaction-analysis/gas-limit-estimate/BNB"

Parameters
Parameter	Description
`chain` path · string · required	ETH, BNB, BASE, STABLE, ARC or RHC; every other chain returns 400.
`from` body · string · optional	Required: the sending wallet, 0x followed by 40 hexadecimal characters.
`to` body · string · optional	Required: the recipient or contract called, 0x followed by 40 hexadecimal characters.
`data` body · string · optional	The calldata, `0x`-prefixed hex of whole bytes. Optional; defaults to `0x` (a plain transfer).
`value` body · string · optional	Native coin sent, in wei, as a decimal string. Optional; defaults to `"0"`.

Response fields

A JSON response. Every field is always present; null means the value could not be established, never zero.

Response fields of What gas limit does this transaction need?
Field	Type	Description
`outcome`	string	`success`: the transaction would run, and `gasLimit` is the limit it needs. `reverted`: it would fail, so no limit is given. `insufficient-funds`: the sender does not hold the `value` sent plus gas, so it could not run at all.
`gasLimit`	integer \| null	The gas limit the chain estimates the transaction needs. `null` unless the outcome is `success`.
`revertReason`	string \| null	The contract's revert message, decoded from the revert data when it is a standard text error, or `Panic(0x..)` for a failed assertion or arithmetic error. `null` when the transaction does not revert, or reverts with a custom error or with no data — read `revertData` for a custom error.
`revertData`	string \| null	The raw revert data, lowercase hex, for decoding a custom error. `null` when the transaction does not revert or reverts with no data.

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