Optimism transaction simulation API
C2Simulate a Optimism transaction against current state before it's signed. Preview asset changes, approvals and reverts so wallets and apps can warn users instead of letting a bad transaction land.
Dry-run against live Optimism state
Submit a transaction for simulation and get back the balance changes, emitted events and revert reason it would produce on Optimism — no gas spent, nothing broadcast.
Protect users pre-signature
Show 'you will receive / you will send' previews and block obviously malicious calls before the user signs, using the same key as the rest of your integration.
Frequently asked
Can I preview asset changes before signing on Optimism?
Yes — simulation returns the net balance and approval changes a transaction would cause.
Does simulation broadcast the transaction?
No — it runs against state without submitting anything to the Optimism network.
Top up, get a key, ship.
Self-serve. Pay in crypto or card. Metered by credits — heavy primitives cost more, simple ones are cheap.
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