A block explorer is the closest thing crypto has to a universal debugger. Whether you are checking if a payment landed, verifying a contract before you interact with it, or reconstructing how a hack drained a protocol, you are using one. The catch: the right explorer depends entirely on the chain and the job.
Here is which explorer to use for each chain, plus the specialised ones for debugging, security, and privacy that most people never discover.
The short answer
- Ethereum and EVM L2s: the Etherscan family — Arbiscan, Basescan, Polygonscan.
- Solana: Solscan for everyday use, SolanaFM for decoding.
- Bitcoin: mempool.space — the gold standard, especially for fees.
- Security / exploit analysis: Phalcon.
- Privacy: Otterscan, self-hosted on your own node.
Ethereum and the EVM: the Etherscan family
Etherscan is the reference explorer for Ethereum, and the same team runs the matching explorers for every major EVM chain: Arbiscan for Arbitrum, Basescan for Base, Polygonscan for Polygon, Optimistic Etherscan for OP Mainnet, plus Lineascan and Scrollscan.
They share one big convenience: since the V2 API consolidation, a single API key works across all of them via a chainid parameter, which is a real win for multichain developers. For contract verification, reading contract state, and everyday transaction lookups, this family is the default. The one thing they are not is open-source or self-hostable.
For that, Blockscout is the open-source explorer of choice for L2s and app-chains — if you are launching a chain and need an explorer you control, it is the standard.
Solana: Solscan and SolanaFM
Solana transactions bundle many instructions across programs, which makes readable decoding the whole game. Solscan is the default most people use — fast, comprehensive, good token and NFT support. SolanaFM leans harder into decoding: it parses and labels complex program interactions better than most, which makes it the pick when you are trying to understand what a transaction actually did rather than just confirm it happened.
Bitcoin: mempool.space
mempool.space is one of the most respected open-source tools in all of crypto. Its signature feature is a live visualisation of the mempool — pending transactions, projected blocks, and real-time fee recommendations — which is invaluable for timing a Bitcoin transaction so you do not overpay. It also does Lightning exploration and mining stats, and because it is open-source, Bitcoin businesses run their own instances for privacy.
Blockchair is the alternative when you want cross-chain search — it indexes 40+ networks with powerful filtering, positioning itself as a search engine for blockchains.
Non-EVM ecosystems
- Cosmos: Mintscan — the canonical multi-chain explorer for the entire IBC ecosystem, with staking, governance, and cross-chain transfer views.
- Polkadot / Substrate: Subscan across the relay chains and parachains.
- Starknet: Starkscan and Voyager — most Starknet devs keep both open.
- Sui and Aptos: Suiscan and Aptos Explorer for the Move-based chains.
- TRON: Tronscan — essential given how much USDT settles on TRON.
The specialists worth knowing
Three explorers do things the mainstream ones cannot:
Debugging: Tenderly is a full development platform whose transaction explorer includes an opcode-level visual debugger — step through every internal call, inspect state changes, and see exactly why a transaction reverted. For developers, this turns painful on-chain debugging into something like using an IDE.
Security: Phalcon, built by BlockSec, is a transaction explorer purpose-built for security analysis — full call traces, state diffs, and fund-flow visualisation. It is the standard tool in post-mortems of DeFi hacks. If you want to understand how an exploit worked, this is where you look.
Privacy: Otterscan is open-source and runs directly on your own Erigon node, so your lookups never leak to a third party. For node operators and privacy maximalists, it is a fast, principled alternative to hosted explorers.
How to use an explorer well
Beyond confirming transactions, the highest-value habit is checking a token or contract before you interact with it. On a scam-heavy chain, an explorer tells you whether a contract is verified (its source is public and matches), how holdings are concentrated, and whether the contract has suspicious functions. Verification status alone filters out a large share of obvious scams.
For developers, the contract read/write interface lets you interact with any verified contract directly from the browser — no code — which is invaluable for debugging and for checking state without writing a script.
Tools referenced in this article
- All block explorers — full category with 26 explorers reviewed
- Etherscan, Solscan, mempool.space, Blockscout
- Phalcon, Otterscan, Mintscan