OP Mainnet is not on Etherscan's free API tier: API access to it starts at the $49 a month Lite plan, while Blockscout's free API covers it. OP Mainnet fees combine an execution gas fee, an L1 data fee and an operator fee, and Standard Bridge withdrawals wait 7 days, so a good explorer shows both the L2 and the L1 side.
Quick answer
Optimistic Etherscan is the best explorer for browsing OP Mainnet, and Blockscout, which runs Optimism's explorer.optimism.io, is the best free API. Use Tenderly to debug transactions.
- 01Optimistic Etherscan: best for browsing
- 02Blockscout: Best free API
- 03Tenderly: best for debugging
- 04Etherscan: Best multichain API key
- 05Dune: best for SQL research
The 5 best OP Mainnet block explorers
Optimistic Etherscan is built by Team Etherscan and lists L1 to L2 and L2 to L1 transactions next to blocks and contracts. Its API is paid only for OP Mainnet, from $49 a month.
- Chains
- OP Mainnet
- Platforms
- Web, API
- Company
- Etherscan (Built by Team Etherscan)
- Chains
- OP Mainnet, OP Sepolia Testnet
- Pricing
- Lite $49/mo, Standard $199/mo, Advanced $299/mo, Professional $399/mo, Pro Plus $899/mo
Pros
- Shows L1 to L2 and L2 to L1 transactions
- Same interface and labels as Etherscan
- One Etherscan API key covers OP Mainnet and other chains
Cons
- OP Mainnet API access is not on the free tier; it starts at $49/month
- API Pro endpoints start at the $199/month Standard plan
Skip it if you need a free API: use Blockscout.
explorer.optimism.io serves Blockscout's OP Mainnet explorer. Its PRO API covers OP Mainnet on the free tier at 5 requests per second and 100K credits a day.
- Chains
- EVM chains
- Platforms
- Web, API
- Pricing
- Builder $49/mo, Pro $199/mo, Business $999/mo, Enterprise custom
- Free plan
- 5 RPS, 100K credits/day
- Open source
- Source-available (Blockscout Software Licence since v11.0.0)
Pros
- Free PRO API: 5 RPS and 100K credits/day
- One API key across 100+ chains
- Free to self-host and modify for your own chain
Cons
- Since v11.0.0 (April 2026) the license is source-available, not open source
- Reselling hosted Blockscout needs a commercial license
- Default call costs 20 credits, so the free tier is about 5,000 calls/day
Skip it if you need an open-source license: since v11.0.0 Blockscout is source-available.
Tenderly lists OP Mainnet (chain ID 10) among 100+ networks and is named in Optimism's block explorer docs. It has a free plan; Node RPC is on paid plans.
- Chains
- EVM networks
- Platforms
- Web, API, SDK
- Free plan
- Free plan available; excludes Node RPC
- Pricing
- Node RPC on paid plans, metered in Tenderly Units (1 to 400 TU per request)
- Chains
- 100+ networks
Pros
- Covers 100+ networks per its docs
- Simulation, debugger, alerts and Node RPC in one dashboard
- Node RPC read calls cost 1 TU each
Cons
- Free plan does not include Node RPC access
- Node RPC capacity is set through the sales team
- Simulation calls over RPC cost 400 TU each
Skip it if you only need to look up a transfer.
One Etherscan API V2 key covers OP Mainnet and 60+ other chains. OP Mainnet is paid tier only, so plan on at least the $49 a month Lite plan.
- Chains
- Ethereum, plus 60+ chains through the API
- Platforms
- Web, API
- Pricing
- Lite $49/mo, Standard $199/mo, Advanced $299/mo, Professional $399/mo, Pro Plus $899/mo
- Free plan
- 3 calls/sec, up to 100,000 calls/day, selected chains, attribution required
- Launched
- August 2015
Pros
- Free API tier: 3 calls/sec, up to 100,000 calls/day
- One API key covers 60+ chains
- Running since August 2015, SOC 2 Type II certified in August 2026
Cons
- Free tier covers only selected chains and needs attribution
- API Pro endpoints start at the $199/month Standard plan
- Robinhood Chain and Arc endpoints move behind the $49 Lite plan on October 16, 2026
Skip it if you only use OP Mainnet on a free budget.
Dune's data catalog includes Optimism among 130+ chains for SQL queries and dashboards. Free access after the trial is view-only.
- Chains
- EVM networks, Solana, Bitcoin, Hyperliquid, Sui, TON, Tron and other non-EVM chains
- Platforms
- Web, API
- Free plan
- View-only after trial: no API exports, data writes or alerts
- Chains
- 100+ chains
- Pricing
- Analyst $75/mo ($65/mo annual); Plus $399/mo ($349/mo annual); Enterprise custom
Pros
- Docs list 100+ indexed chains
- No credits charged for SQL syntax errors or engine failures
- Plus plan allows 200 requests per minute on read endpoints
Cons
- Free tier is view-only, with no API access, data writes or alerts
- Analyst plan data export costs 10 credits per MB, versus 2 on Plus
- Analyst plan storage is capped at 1 GB
Skip it if you need API exports without paying.
Not on this list
Superscan by Routescan: Optimism's docs list it, but we could not confirm its API limits or pricing on Routescan's own pages.
OKLink: Terms exclude US residents: its Terms of Services list the US and all US territories as restricted territories.
OP Mainnet Block Explorers ranked
Select a name to jump to its review.
“Not verified” means we could not confirm the value on the project’s own pages.
How we rank OP Mainnet block explorers
- 01OP Mainnet coverage: support confirmed on the tool's own page or Optimism's docs.
- 02Free API access: whether OP Mainnet is on the free tier.
- 03L2 detail: L1 to L2 and L2 to L1 message views.
- 04Paid entry plan: lowest monthly price, in USD.
No project paid to be listed or ranked. Full rules: methodology.
What we did not test
- We did not open accounts, deposit money or place trades with these services.
- We did not audit smart contracts, reserves or security claims ourselves; we report what the project and its auditors publish.
- Fees, limits and availability change; the list date shows when we last checked them.
Rubric last updated Oct 1, 2026. Crypto assets are not insured by the FDIC or SIPC, and you can lose all the money you put in. This page is educational content, not financial advice.
How to choose
01Know the three fees
An OP Mainnet fee is execution gas plus an L1 data fee plus, since Isthmus, an operator fee. Explorers break these out.
02Withdrawals take 7 days
Standard Bridge withdrawals to Ethereum wait 7 days for fault proofs. Track the L2 side here and the L1 side on Etherscan.
03Pick your API by budget
On Etherscan, OP Mainnet needs a paid plan; Blockscout's free tier covers it.
Who should skip all of these
- Other OP Stack chains such as Base: each has its own explorer.
- Portfolio tracking across chains: see our portfolio trackers list.
Bottom line
Browse on Optimistic Etherscan or explorer.optimism.io; build on Blockscout's API if you want OP Mainnet data for free.
Budget $49 a month if you want OP Mainnet through Etherscan's API.
Educational content, not financial advice. Crypto assets are volatile; do your own research.
FAQ
What is the official OP Mainnet explorer?
±
explorer.optimism.io serves Blockscout's OP Mainnet explorer. Optimism's docs also list Etherscan, Superscan by Routescan and Tenderly.
Is the Optimistic Etherscan API free?
±
No. Etherscan's supported chains page marks OP Mainnet as paid tier only; the Lite plan costs $49 a month.
Why does my OP withdrawal take a week?
±
Standard Bridge withdrawals to Ethereum wait 7 days for fault proofs.
What makes up an OP Mainnet fee?
±
An execution gas fee, an L1 data fee and, since the Isthmus upgrade, an operator fee.
Is there a free API for OP Mainnet data?
±
Yes: Blockscout's PRO API covers OP Mainnet on its free tier at 5 requests per second and 100,000 credits a day, and most calls cost 20 credits. Etherscan's API covers OP Mainnet only on paid plans, from $49 a month for Lite.
What changed in this list
2026-09-26First version: 6 picks, each confirmed as usable on the chain from its card or its own page.
2026-09-26Moved OKLink to Not on this list: its terms exclude US residents
2026-10-01Added a FAQ on free API access for OP Mainnet.
Who made this page
✓
Fact check
Checked against 9 sourcesLast check: Oct 1, 2026
A value we could not confirm on the project’s own pages is marked “Not verified” instead of estimated.
How we review