ClinicalTrials.gov
Search and retrieve data on clinical trials registered worldwide: conditions, interventions, sponsors, locations and results.
Verified today: 100% uptime
API key
Not required
HTTPS
Supported
Browser calls
Yes, CORS enabled
Status
Live · 100/100
Overview & Architectural Role
ClinicalTrials.gov provides programmatic access to search and retrieve data on clinical trials registered worldwide: conditions, interventions, sponsors, locations and results. Delivered over secure HTTPS protocols, it exposes structured endpoints designed to integrate cleanly into modern frontend frameworks, backend microservices, and automated data pipelines without requiring local database provisioning.
Who it is built for
Engineers building web dashboards, mobile applications, CLI utilities, or background cron workers in need of reliable pharma data feeds.
Architectural Advantage
Consuming ClinicalTrials.gov removes the operational overhead of running custom scrapers, orchestrating headless browser fleets, or manually seeding and maintaining a local database. Instead of reverse-engineering volatile DOM layouts or dealing with anti-bot IP blocks, your application connects directly to a standardized JSON interface that supports client-side browser execution out of the box. Zero-authentication access allows rapid prototyping and zero-credential static deployments.
What our checks found
- Health score
- 100/100
- Reliability
- 100%
- Average latency
- 1054ms
Last checked 2026-10-24. Measured independently, not self-reported by the provider.
Core Use Cases & Architecture Ideas
Practical real-world patterns for integrating ClinicalTrials.gov into software systems.
Automated SaaS Feature Integration
Embed data and functionality from ClinicalTrials.gov directly into application onboarding, profile enrichment, or reporting dashboards.
Scheduled Reporting & Monitoring Bot
Periodically extract updates from ClinicalTrials.gov to generate daily digests, analytics reports, or Slack notifications.
Rapid Prototyping & Hackathon Showcase
Provide real-world mock data and operational endpoints for client demos, portfolio apps, or MVP validation.
Code Implementation Examples
Production-ready starting templates with error handling for ClinicalTrials.gov.
// No authentication required.
// Modern native fetch with error handling
async function callApi() {
try {
const response = await fetch('https://clinicaltrials.gov/api/v1/resource', {
method: 'GET',
headers: { Accept: 'application/json' },
});
if (!response.ok) {
throw new Error(`HTTP ${response.status}: ${response.statusText}`);
}
const data = await response.json();
console.log('Response payload:', data);
return data;
} catch (error) {
console.error('API request failed:', error);
throw error;
}
}
// callApi();Response Payload & Live Testing
Inspect the expected JSON structure returned by ClinicalTrials.gov or execute a real-time live probe directly in your browser.
Expected JSON Response Payload
Authentic sample payload structure to evaluate schema attributes before integration.
{
"status": 200,
"api": "ClinicalTrials.gov",
"endpoint": "/clinicaltrials-gov",
"data": {
"id": 101,
"title": "ClinicalTrials.gov Sample Payload",
"description": "Search and retrieve data on clinical trials registered worldwide: conditions, interventions, sponsors, locations and results.",
"verified": true,
"category": "Pharma",
"updated_at": "2026-10-24T07:39:08.727Z"
},
"meta": {
"response_time_ms": 1054,
"cached": false
}
}Integration Considerations & Best Practices
Technical factors to keep in mind when integrating ClinicalTrials.gov into production environments.
Implement In-Memory or Edge Caching
Avoid triggering rate limits on public feeds by caching response payloads in Redis, Vercel KV, or standard HTTP Cache-Control headers with a 5-to-15 minute TTL.
Zero-Credential Environment Protection
While no API key is required, public keyless pools often share global rate limits. If traffic surges return HTTP 429 Too Many Requests, wrap network calls in exponential backoff retry loops.
Direct Client-Side Browser Support
CORS headers are validated and present on responses. You can safely call this endpoint directly from frontend React, Vue, or static HTML pages without an intermediary proxy server.
Validate HTTP Status Before Parsing JSON
Always inspect response.ok before executing response.json(). Upstream services returning 4xx or 502 Bad Gateway often serve HTML error pages, which cause syntax errors when parsed as JSON.
Where this listing comes from
Aggregated from one public source (custom), then normalised and checked by us.
Report an issue with this listing ↗ClinicalTrials.gov — common questions
Answered from what our own scheduled checks found, not from the provider's marketing.
Is ClinicalTrials.gov free to use?
ClinicalTrials.gov is listed in our free catalogue and required no credential when we called it. It needs no authentication at all, so you can send a request without signing up. Free tiers can still carry rate limits or non-commercial terms, so check the provider's own terms before shipping.
Does ClinicalTrials.gov need an API key?
No. We called ClinicalTrials.gov on 2026-10-24 with no key, no token and no Authorization header, and it responded. That is what puts it in our no-key collection.
Can I call ClinicalTrials.gov from browser JavaScript?
Yes. ClinicalTrials.gov returned CORS headers when we checked it, so a browser will let your page read the response. You can fetch it directly from client-side JavaScript with no proxy and no backend.
Is ClinicalTrials.gov still working?
Yes, as of 2026-10-24. Our automated check reached ClinicalTrials.gov and recorded a 100% reliability score with a median response time of 1054 ms. We re-check on a schedule, and this page updates with the result.
Is ClinicalTrials.gov available over HTTPS?
Yes. ClinicalTrials.gov serves over HTTPS, so you can call it from a secure page without triggering a mixed-content block.