Run cURL Commands Online Free

Test APIs, websites, and web services directly in your browser. Professional cURL command runner with detailed response analysis, headers inspection, and timing data. No downloads or plugins required.

Online cURL Command Runner

Executing cURL command...

Please wait while we process your request

Usage Notice: This tool is for educational and testing purposes. Please use responsibly and only test URLs you own or have permission to access. All requests are monitored for security.

Response Results

No response body available

Execute a cURL command to see the response body here

No headers available

HTTP response headers will appear here after execution

No raw response available

Complete raw cURL output will be displayed here

No timing information available

Detailed timing breakdown will appear here after execution

What is cURL Command?

cURL (Client URL) is a powerful command-line tool and library for transferring data using various network protocols including HTTP, HTTPS, FTP, and many others. Originally developed by Daniel Stenberg in 1997, cURL has become an essential tool for developers, system administrators, and API testers worldwide.

Key Features of cURL:

  • Multi-Protocol Support: HTTP, HTTPS, FTP, FTPS, SCP, SFTP, LDAP, and more
  • Authentication Methods: Basic, Digest, NTLM, OAuth, and custom authentication
  • Data Transfer: Upload and download files, send POST data, handle forms
  • SSL/TLS Support: Secure connections with certificate verification
  • Proxy Support: HTTP, SOCKS4, and SOCKS5 proxy protocols
  • Cookie Handling: Automatic cookie jar management

Why Use Our Online cURL Runner?

Our online cURL command runner eliminates the need to install cURL locally. Test APIs instantly, debug HTTP requests, and analyze responses with detailed timing data - all from your browser without any setup required.

Common cURL Use Cases:

  1. API Testing: Test REST APIs, send JSON payloads, verify responses
  2. Web Scraping: Download web pages, extract data from websites
  3. File Transfer: Upload/download files to/from servers
  4. Performance Testing: Measure response times and analyze bottlenecks
  5. Authentication Testing: Verify login systems and secure endpoints
  6. Header Analysis: Inspect HTTP headers for debugging

How to Run cURL Commands Online

Running cURL commands online has never been easier with our web-based tool. Follow these simple steps to execute your first cURL command:

Step-by-Step Guide:

  1. Enter Command: Type or paste your cURL command in the text area above
  2. Execute: Click the "Execute cURL Command" button
  3. Analyze Results: View response in organized tabs (Body, Headers, Raw, Timings)
  4. Copy & Share: Use copy buttons to save results for documentation

Basic cURL Command Examples:

# Simple GET request curl -X GET https://httpbin.org/get # POST request with JSON data curl -X POST https://httpbin.org/post \ -H "Content-Type: application/json" \ -d '{"name": "John", "email": "john@example.com"}' # GET request with custom headers curl -X GET https://api.github.com/users/octocat \ -H "User-Agent: MyApp/1.0" \ -H "Accept: application/json" # HEAD request to check headers only curl -I https://httpbin.org/get # POST form data curl -X POST https://httpbin.org/post \ -d "name=John&email=john@example.com"

Security & Privacy

Our online cURL runner processes requests securely. No commands or responses are stored on our servers. All data transmission is encrypted using HTTPS, and we implement strict rate limiting to prevent abuse.

cURL Command Syntax & Options

Understanding cURL syntax is essential for effective API testing and web service interaction. Here's a comprehensive guide to the most commonly used cURL options and their usage.

Basic Syntax:

curl [options] [URL]

Essential cURL Options:

  • -X, --request: Specify HTTP method (GET, POST, PUT, DELETE, etc.)
  • -H, --header: Add custom headers to the request
  • -d, --data: Send data in the request body (typically for POST)
  • -i, --include: Include response headers in output
  • -I, --head: Fetch headers only (HEAD request)
  • -o, --output: Write output to file instead of stdout
  • -v, --verbose: Enable verbose output for debugging
  • -s, --silent: Silent mode (no progress bar)
  • -w, --write-out: Display custom information after transfer
  • --max-time: Maximum time allowed for transfer

Advanced Examples:

# Upload file with POST curl -X POST https://httpbin.org/post \ -F "file=@document.pdf" \ -F "description=Important document" # Basic authentication curl -X GET https://httpbin.org/basic-auth/user/pass \ -u user:pass # Follow redirects with cookies curl -X GET https://httpbin.org/redirect/3 \ -L -c cookies.txt -b cookies.txt # Custom timeout and retry curl -X GET https://httpbin.org/delay/2 \ --max-time 30 \ --retry 3 \ --retry-delay 1

Testing Different Content Types:

  • JSON API: Use -H "Content-Type: application/json"
  • Form Data: Use -H "Content-Type: application/x-www-form-urlencoded"
  • File Upload: Use -H "Content-Type: multipart/form-data"
  • XML Data: Use -H "Content-Type: application/xml"

Professional API Testing with cURL

Our online cURL runner is the perfect tool for comprehensive API testing. Whether you're developing REST APIs, testing third-party integrations, or debugging web services, our platform provides all the features you need.

API Testing Best Practices:

  1. Start with Simple GET: Begin testing with basic GET requests to verify connectivity
  2. Verify Headers: Check Content-Type, Authorization, and custom headers
  3. Test Error Scenarios: Send invalid data to test error handling
  4. Monitor Performance: Use timing data to identify bottlenecks
  5. Document Results: Save successful requests for team documentation

Common API Testing Scenarios:

# Test REST API endpoints curl -X GET https://jsonplaceholder.typicode.com/posts/1 # Create new resource curl -X POST https://jsonplaceholder.typicode.com/posts \ -H "Content-Type: application/json" \ -d '{ "title": "My New Post", "body": "This is the post content", "userId": 1 }' # Update existing resource curl -X PUT https://jsonplaceholder.typicode.com/posts/1 \ -H "Content-Type: application/json" \ -d '{ "id": 1, "title": "Updated Post Title", "body": "Updated content", "userId": 1 }' # Delete resource curl -X DELETE https://jsonplaceholder.typicode.com/posts/1

Response Analysis Features:

  • JSON Formatting: Automatically formatted JSON responses with syntax highlighting
  • Header Inspection: Complete HTTP header analysis in table format
  • Timing Breakdown: DNS, connect, TLS, send, wait, and receive timings
  • Status Code Analysis: Clear success/error indication with HTTP status codes
  • Copy Functions: Easy copying of responses for documentation

Advanced Features

Our tool automatically adds security headers, timeout protection, and provides detailed timing analysis. Perfect for performance testing and identifying slow API endpoints.

Frequently Asked Questions

cURL is a command-line tool for transferring data using various protocols. It's essential for API testing, web scraping, file transfers, and debugging HTTP requests. Our online version eliminates the need for local installation while providing the same powerful features.

On Windows 10/11, cURL is pre-installed. Open Command Prompt or PowerShell and type cURL commands directly. For older Windows versions, download cURL from the official website. Alternatively, use our online tool which works on any platform including Windows, Mac, and Linux.

Yes, our tool implements multiple security measures: HTTPS encryption, command validation, rate limiting, and no data storage. We don't save your commands or responses. However, avoid sending sensitive data like passwords or API keys through any online tool.

Absolutely! Use the format: curl -X POST https://api.example.com/data -H "Content-Type: application/json" -d '{"key": "value"}'. Our tool supports all HTTP methods and content types, with automatic JSON formatting in the response.

Our tool focuses on cURL command execution with detailed response analysis, while Postman is a comprehensive API development environment. Use our tool for quick cURL testing, command verification, and when you prefer command-line syntax over GUI interfaces.

Yes! Our tool provides detailed timing breakdowns including DNS resolution, connection time, TLS handshake, sending, waiting, and receiving phases. This helps identify performance bottlenecks in your API calls.