# Subscan API | PubFi Discovery

> Subscan API is tracked as an on-chain state and governance source for Polkadot coverage. Explorer and indexed Substrate chain API for accounts, extrinsics, governance, staking, and asset data.

Source: Discovery catalog fixtures consumed by the public Discovery routes.
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Agent availability rule: raw claim-safe status is preserved for provenance, but actionability uses effective agent availability. Degraded pages require revalidation even when the raw status names a gateway, x402, or MCP surface.

Canonical HTML URL: https://pubfi.ai/discovery/api/subscan
Markdown URL: https://pubfi.ai/discovery/api/subscan.md
Title: Subscan API | PubFi Discovery
Provider: Subscan
One-liner: Explorer and indexed Substrate chain API for accounts, extrinsics, governance, staking, and asset data.
Long description: Subscan API is tracked as an on-chain state and governance source for Polkadot coverage. Explorer and indexed Substrate chain API for accounts, extrinsics, governance, staking, and asset data.
SEO description: Subscan API is an indexed Substrate and Polkadot data source for accounts, extrinsics, governance, staking, and asset data, with PubFi status labels.
Public status: degraded
Directory status: coming soon
Raw claim-safe status: gateway_available (Gateway available)
Raw claim-safe CTA: Call gateway
Effective agent availability: needs_reverification (Needs re-verification)
Effective agent CTA: Reverify before live use
Agent actionability: requires revalidation
Agent availability reason: The source is degraded, so raw callable or tooling status is not treated as actionable.
PubFi gateway readiness: gateway_available (PubFi gateway route documented; reverify before live use)
PubFi gateway summary: The gateway readiness catalog has a production-callable PubFi route for this source, but the Discovery source profile is not current. Agents should reverify upstream docs, commercial terms, and gateway behavior before live use.
PubFi gateway guidance:
- Supported route pattern: /api/gateway/subscan/{network}/{endpoint...}
- Network convention: The network segment maps to the upstream Subscan chain host, such as polkadot or acala.
- Accepted PubFi auth headers: Authorization: Bearer <PubFi API key> or X-PubFi-Api-Key: <PubFi API key>.
- Upstream credential boundary: SUBSCAN_KEY remains server-side in PubFi; do not send upstream provider keys from agent clients.
- Gateway docs or quickstart: https://support.subscan.io/doc-362600
PubFi gateway route examples:
- Current block time: GET /api/gateway/subscan/polkadot/api/now (network polkadot; upstream /api/now)
```bash
curl --location 'https://pubfi.ai/api/gateway/subscan/polkadot/api/now' \
  --header 'Authorization: Bearer <PubFi API key>'
```
- Account tokens: POST /api/gateway/subscan/polkadot/api/scan/account/tokens (network polkadot; upstream /api/scan/account/tokens)
```bash
curl --location 'https://pubfi.ai/api/gateway/subscan/polkadot/api/scan/account/tokens' \
  --header 'Authorization: Bearer <PubFi API key>' \
  --header 'Content-Type: application/json' \
  --data '{
  "address": "13YMK2efcJncYrXsaJCvHbaaDt3vfubdn75r4hdVxcggU4n2"
}'
```
- Account tokens on Acala: POST /api/gateway/subscan/acala/api/scan/account/tokens (network acala; upstream /api/scan/account/tokens)
```bash
curl --location 'https://pubfi.ai/api/gateway/subscan/acala/api/scan/account/tokens' \
  --header 'Authorization: Bearer <PubFi API key>' \
  --header 'Content-Type: application/json' \
  --data '{
  "address": "13YMK2efcJncYrXsaJCvHbaaDt3vfubdn75r4hdVxcggU4n2"
}'
```
Primary keyword: subscan api
Keyword cluster: best_api
Primary chain: polkadot
Primary category: on-chain-state
Page tier: tier_1
Official site URL: https://subscan.io/
Last verified: 2026-06-02T00:00:00Z
Guardrail: Claim-safe statuses distinguish source profiles, evaluation-only pages, requested integrations, and available gateway/tooling surfaces without exposing paid procurement, approval, or provider-fetching flows.
Data types: accounts, extrinsics, governance, staking, assets
Protocols: rest
Auth methods: api key
REST support: yes
GraphQL support: not listed
WebSocket support: not listed
Streaming support: not listed
Webhook support: not listed
Pricing model: freemium
Commercial status: partial (Free API limit verified; paid plan pricing is plan-specific)
Free tier: Free API plan allows one API key with a 5 req/sec limit.
Starting price: contact sales
Pricing URL: commercial docs https://support.subscan.io/doc-360177
Free rate limit: 5 req/sec
Paid rate limit: A higher Subscan API plan can be selected, but public paid prices and paid quotas are not published in the support article.
Feature flags: none
Status page: not listed
Has SDK: not listed
SDK languages: none
Documentation URL: https://support.subscan.io/
Documentation quality score: not listed
Reviewed at: 2026-06-02T04:00:00Z
Signed off at: 2026-06-02T05:00:00Z
Demand signals: on-chain state source coverage (unproven)
Category hubs: On-chain state https://pubfi.ai/discovery/category/on-chain-state, Governance https://pubfi.ai/discovery/category/governance
Chain hubs: Polkadot https://pubfi.ai/discovery/chain/polkadot
Official source links:
- Official site: https://subscan.io/
- Provider docs: https://support.subscan.io/
- Subscan API plan and rate-limit support article: https://support.subscan.io/doc-360177
- PubFi status: https://pubfi.ai/openapi/subscan-openapi.json
Alternative APIs:
- SubSquid: https://pubfi.ai/discovery/api/subsquid (raw public_source_profile; effective public_source_profile; detail public/featured-export)
- SubQuery Network: https://pubfi.ai/discovery/api/subquery (raw public_source_profile; effective public_source_profile; detail public/featured-export)
- OnFinality: https://pubfi.ai/discovery/api/onfinality (raw public_source_profile; effective needs_reverification; detail public/markdown-exported)
Key facts:
- Primary query: subscan api (source https://support.subscan.io/)
- Primary coverage: Substrate accounts, extrinsics, governance, staking, and asset data (source https://subscan.io/)
- Discovery category: On-chain state and governance (source https://subscan.io/)
- Auth model: API-key authentication is required for live Subscan API use (source https://support.subscan.io/doc-360177)
- Commercial fact: Free API access is documented with one API key and a 5 req/sec limit; paid-plan pricing is not public in the support article (source https://support.subscan.io/doc-360177)
- PubFi status: PubFi gateway route documentation exists for Subscan; upstream account, auth, and route limits still apply (source https://pubfi.ai/openapi/subscan-openapi.json)
Best for candidates:
- Substrate account and extrinsic lookups
- Polkadot and parachain governance monitoring
Not ideal for candidates:
- Generic EVM RPC workloads
- Market-wide price aggregation
Use case candidates:
- Track account activity across Substrate chains
- Read governance and staking state for Polkadot ecosystem apps
Implementation note metadata:
- auth severity medium
- rate limits severity medium
Quick start metadata: style rest; language http; method GET; path https://acala.api.subscan.io/api/now; requires auth yes
Capabilities:
- Subscan API on-chain state coverage: requested; auth api_key; procurement free_requires_auth; coverage polkadot; outputs chain_state_record (chain_slug, address_or_entity, record_type, captured_at)
- Subscan API governance coverage: requested; auth api_key; procurement free_requires_auth; coverage polkadot; outputs governance_record (chain_slug, proposal_id, status, captured_at)