freeapis

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_key query parameter.

⚠️ Gotcha (verified): invalid keys return HTTP 200 with success:false — check the success field.

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.

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