Multicall Builder
Pack reads into one Multicall3 aggregate3 payload.
Runs offline
On failure
List calls as address, calldata — one per line — to encode a Multicall3 batch.
About multicall builder
Multicall3 batches many read calls into a single RPC request, which is how block explorers and portfolio trackers fetch hundreds of balances without hundreds of round trips. It is deployed at the same address on most chains. This page builds that payload — the encoded calldata and the address to send it to — and stops there; sending it is a job for your node or your wallet. The allowFailure flag decides whether one bad call takes the whole batch down or simply reports its own failure.
Common questions
What is Multicall3 used for?
Packing many read calls into one request so a dashboard can fetch balances, allowances and prices without dozens of round trips. aggregate3 can also mark individual calls as allowed to fail without reverting the batch.
Does building a multicall move funds?
Not by itself. This page builds the payload; executing a state-changing batch still requires a signed transaction. Read-only aggregate calls need no signature and change nothing.
Why use aggregate3 instead of separate RPC calls?
Latency and consistency. One round trip returns one block view of many contracts, which matters when comparing numbers that should be from the same moment. Separate calls can straddle a block boundary.