Watchdata
Provide simple and reliable API access to Ethereum blockchain
- Authentication
- API Key
- HTTPS
- Yes
- CORS
- Unknown
- Category
- Blockchain
- Data source
- public-apis + marcelscruz
- Documentation / URL
- https://docs.watchdata.io
Overview
Watchdata provides Ethereum API access — key-based (a missing key returns 401, verified).
Quick Start
Balance (replace YOUR_KEY):
curl "https://api.watchdata.io/v2/eth/balance/0x0?api_key=YOUR_KEY"Authentication
- Register at watchdata.io → API key.
- Send it as the
api_keyquery parameter (missing → 401, verified).
Rate Limits & Notes
- Free tier with limits (check the docs); paid plans scale.
- Ethereum data.
FAQ
Is Watchdata free? Free tier with limits; more is paid.
Why 401? An API key is required (verified).
What’s the auth style?
api_key query parameter.
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