Blockscout vs Helium

Blockscout is the open-source, EVM-compatible block explorer behind dozens of public chain explorers (Ethereum mainnet, its L2s, and more), and its REST v2 API exposes the same block, address, token, and transaction data that powers those explorer UIs. No signup or API key is required for the per-instance hosted public REST API, though anonymous callers are rate-limited per endpoint (confirmed live: `x-ratelimit-limit` varies by route, e.g. 180 on an address lookup vs. 10 on `/stats`); docs.blockscout.com also flags this per-instance API for deprecation in favor of a separate, paid, API-key-gated multichain "PRO API," though the free per-instance API this entry tracks was still live and keyless as of this run's probe. Every response is JSON.

Helium's original Layer-1 blockchain was retired in an April 2023 migration to Solana, and the network's chain data now ships only as bulk Postgres/CSV snapshots over torrent or a requestor-pays S3 bucket rather than a queryable API. The one remaining live HTTP endpoint is the free Entity API, which returns a Hotspot's owner, asserted (H3-obfuscated) location, and on-chain asset IDs by wallet public key. It carries no uptime guarantee and is meant for light lookups, not production traffic.