OpenSea API

OpenSea API provides data access to the world's largest NFT marketplace — collections, individual NFT details, listings, offers, transaction history, ownership.

Visit site ↗Documentation ↗Health checked 9h ago

Use it when

Broadest NFT market coverage (Ethereum/Polygon/Solana/Klaytn, etc.)

Watch for

OpenSea market share has been squeezed by Blur and others since 2023

First check

Apply for API key at opensea.io/account/settings. GET https://api.opensea.io/api/v2/chain/ethereum/contract/{address}/nfts -H "X-API-KEY: ..."

Auth

api_key

CORS

HTTPS

Yes

Signup

Latency

466 ms

Protocol

REST, GraphQL

Pricing

freemium

Uptime · 30-day window

Probes: 1Uptime: 100%Avg latency: 466ms

About this API

OpenSea is an NFT marketplace founded 2017, absolutely dominant during the 2021-2022 NFT boom ($100M+ daily volume). Lost market share to competitors like Blur (targeting pro NFT traders with zero fees + token incentives) since 2023, but still the highest-traffic NFT platform. API provides: browse collections (sorted by floor price, volume), all NFTs in a specific collection, specific NFT details (with metadata and listings), wallet NFT holdings, transaction history. Third-party NFT apps (wallets, aggregators, analytics dashboards) use this API heavily. Note: v2 API (launched 2023) differs significantly from v1; old code may need migration.

What you can build

1NFT wallet apps displaying user NFTs
2Third-party NFT browsers/aggregators
3NFT price tracking dashboards
4NFT project analytics
5OpenSea floor price real-time display

Strengths & limitations

Strengths

Broadest NFT market coverage (Ethereum/Polygon/Solana/Klaytn, etc.)
Complete historical data
Officially licensed data

Limitations

OpenSea market share has been squeezed by Blur and others since 2023
Strict rate limits (free 5 req/s)
Some sensitive endpoints require review

Example request

Generic template — replace <endpoint> with the real path from the docs.

curl https://opensea.io/<endpoint> \
  -H "Authorization: Bearer $API_KEY"
# Some providers use X-Api-Key instead — verify in the docs.

Getting started

Apply for API key at opensea.io/account/settings. GET https://api.opensea.io/api/v2/chain/ethereum/contract/{address}/nfts -H "X-API-KEY: ..."

FAQ

OpenSea vs. Reservoir.tools?+

Reservoir aggregates multiple NFT markets (OpenSea + Blur + LooksRare, etc.) — more complete data. OpenSea API only has OpenSea's own data but is officially authoritative.

How do I get an API key?+

Apply in OpenSea account. Simple use cases auto-approved; high-volume commercial may require review.

Technical details

CORS: ?HTTPS: YesSignup: ?Open source: No

Auth type: api_key
Pricing: freemium
Rate limit: free 5 req/s；Pro 更高
Protocols: REST, GraphQL
SDKs: javascript, typescript, python
Response time: 466 ms
Last health check: 5/12/2026, 7:38:01 AM