eth_getTransactionCount on Optimism
Returns the number of transactions sent from an address — i.e. the next nonce to use. Use the "pending" tag to account for in-flight transactions.
The latest tag counts only mined txs; pending includes in-flight ones — always use pending to pick the next nonce or you'll collide with your own unconfirmed transactions.
Optimism endpoint (public — no key)
https://rpc.nodeflare.app/op/publicMethod
eth_getTransactionCount
Cost
2 CU
Chain ID
10
Block time
~2 s
Finality
~2 s soft · L1-final ~13 min
Transactions on Optimism
As the OP Stack pioneer, Optimism transactions carry an L1 data fee on top of L2 execution. Read the receipt's l1Fee fields for the true total cost.
Parameters
[address, blockNumber|tag]cURL
curl https://rpc.nodeflare.app/op/public \
-X POST \
-H 'content-type: application/json' \
-d '{"jsonrpc":"2.0","method":"eth_getTransactionCount","params":["0x0b2c639c533813f4aa9d7837caf62653d097ff85", "latest"],"id":1}'The example targets the USDC contract on Optimism — you can run it as-is.
ethers.js
import { ethers } from 'ethers';
const provider = new ethers.JsonRpcProvider(
'https://rpc.nodeflare.app/op/public'
);
const result = await provider.send('eth_getTransactionCount', ["0x0b2c639c533813f4aa9d7837caf62653d097ff85", "latest"]);Try it live
Runs the example above against the public Optimism endpoint — straight from your browser.
eth_getTransactionCount on Optimism — FAQ
How do I call eth_getTransactionCount on Optimism?
POST a JSON-RPC 2.0 request with "method": "eth_getTransactionCount" to NodeFlare's Optimism endpoint at https://rpc.nodeflare.app/op/public. No API key is required for the public endpoint.
What does eth_getTransactionCount cost on the free tier?
eth_getTransactionCount is weighted at 2 compute units per call. The free tier includes 3,000,000 CU/month, so that is roughly 1,500,000 eth_getTransactionCount calls per month — no credit card.
Is eth_getTransactionCount available on the public Optimism endpoint?
Yes. eth_getTransactionCount works on the public Optimism endpoint (https://rpc.nodeflare.app/op/public) with no API key, limited to 1 request per 10 seconds per IP. A free key adds an authenticated endpoint with higher limits.
Anything Optimism-specific to know when using eth_getTransactionCount?
As the OP Stack pioneer, Optimism transactions carry an L1 data fee on top of L2 execution. Read the receipt's l1Fee fields for the true total cost.
Call eth_getTransactionCount on Optimism with a free key
3,000,000 compute units/month for supported methods across every listed chain. Method, rate and concurrency limits apply. No credit card.
Get your free API key →eth_getTransactionCount on other chains