Userstack
Secure User-Agent String Lookup JSON API
- Authentication
- OAuth
- HTTPS
- Yes
- CORS
- Unknown
- Category
- Development
- Data source
- public-apis
Overview
Userstack parses user-agent strings — key-based (an invalid key returns HTTP 200 with success:false, verified).
Quick Start
Detect (replace YOUR_KEY):
curl "https://api.userstack.com/api/detect?access_key=YOUR_KEY&ua=test"
{ "success": false, "error": { "code": 101, "type": "invalid_access_key", "info": "You have not supplied a valid API Access Key." } }
Authentication
- Register at userstack.com → API key.
- Send it as the
access_keyquery parameter.
⚠️ Gotcha (verified): invalid keys return HTTP 200 with
success:false— check thesuccessfield.
Rate Limits & Notes
- Free tier: 1,000 requests/month (check the docs); paid plans scale.
- UA parsing.
FAQ
Is Userstack free? Free tier: 1,000 requests/month; more is paid.
Why 200 with success:false?
Errors come as 200 + success:false (verified) — check success.
What’s the auth style?
access_key query parameter.
More in Development
| API | Auth | HTTPS | CORS | |
|---|---|---|---|---|
| 24 Pull Requests Project to promote open source collaboration during December | No auth | Yes | Yes | ↗ |
| Abacus Free and simple counting service. You can use it to track page hits and specific events | No auth | Yes | Unknown | ↗ |
| Agent Gateway 34+ AI agent infrastructure services including memory, wallets, and scheduling | API Key | Yes | Unknown | ↗ |
| AgentDeals Search and compare developer free tiers, startup credits, and pricing changes | No auth | Yes | Unknown | ↗ |
| Agify.io Estimates the age from a first name | No auth | Yes | Yes | ↗ |