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APIRequest Builder

Request Builder

HTTP request builder. Build API requests visually and generate code snippets for fetch, axios, curl, Python requests.

100% browser-based — your data never leaves your device

Visual BuilderMulti-LanguageAuth SupportOne-Click Copy
HomeAPIRequest Builder
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Tool

Build HTTP requests interactively and generate code snippets in multiple languages.

Request Builder

Build HTTP requests visually and generate code snippets for fetch, axios, curl, Python, and more.

Visual Builder

Build requests with form fields for URL, method, headers, body, and params.

Multi-Language

Generate code for fetch, axios, curl, Python requests, and more.

Auth Support

Basic auth, Bearer token, API key header generation.

One-Click Copy

Copy generated code snippets directly to clipboard.

fetch(class="hljs-string">"https://api.example.com/data", {
  method: class="hljs-string">"GET",
  headers: {
  class="hljs-string">"Content-Type": class="hljs-string">"application/json",
  class="hljs-string">"Authorization": class="hljs-string">"Bearer token"
  },
})
  .then(res => res.json())
  .then(data => console.log(data))
211 chars19 words9 lines

Frequently Asked Questions

JavaScript (fetch, axios), Python (requests), cURL, Go, and Rust are currently supported. More languages are planned.

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How to Use the Free Client-Side Request Builder

Instead of hand-writing HTTP calls and getting the syntax wrong, this tool lets you compose a request visually and then hands you production-ready code. Every header, query parameter, and body field you fill in is converted into an idiomatic snippet in the language you pick. The flow is straightforward:

  1. Fill in the URL, select the HTTP method, and add headers, query parameters, and a request body using the visual form fields.
  2. Configure authentication by choosing Basic Auth, Bearer Token, or API Key and entering your credentials.
  3. Select your target language — JavaScript fetch, axios, Python requests, cURL, Go, or Rust.
  4. Click Copy to place the ready-to-use snippet on your clipboard and paste it into your project.

When to Use Request Builder

This tool fits two common workflows. The first is rapid integration: you need a fetch call in a web app, a requests call in a Python script, or a cURL command to verify something in the terminal, and you want them generated correctly the first time rather than transcribed from memory. The visual form prevents the classic mistakes, like forgetting the Content-Type header or failing to stringify a JSON body in fetch.

The second workflow is exploring authentication. Because the builder supports Basic Auth, Bearer tokens, and API key headers, you can prototype how a protected endpoint behaves with each credential type before committing the logic to code. That is valuable when a service supports several auth methods and you want to compare behavior without editing code between attempts. Teams spread across different stacks benefit too, since one visual configuration can be exported as JavaScript, Python, Go, or Rust to match each developer's environment.

Request Builder Tips and Best Practices

  1. Always include Content-Type: application/json on POST, PUT, and PATCH requests with a JSON body, or the server may refuse to parse the payload.
  2. When generating JavaScript fetch, stringify your object with JSON.stringify() before passing it as the body — fetch requires the body to be a string.
  3. Generate snippets in the language your team actually uses, and reuse the multi-language export when the same request needs to exist in several stacks.
  4. Test each auth type visually before committing: switch between Basic, Bearer, and API Key to confirm which one the endpoint accepts.

Why Client-Side Privacy Matters for Building Authenticated Requests

When you build a request that carries a Bearer token or an API key, that credential becomes part of the generated code you copy into your project. If the builder ran on a remote server, every token you entered could be captured in its logs. This tool performs all request construction and code generation locally in your browser, so the credentials you type never travel anywhere.

That is especially important for developers working with production tokens or shared service accounts. Generating authenticated code snippets without a single credential leaving the device means you can paste a real token into the form, copy out working code, and be confident that no third party recorded either the token or the endpoint it was meant for.

How to Use Request Builder

1

Build your request

Fill in the URL, select HTTP method, add headers, query parameters, and request body using the visual form fields.

2

Configure authentication

Choose from Basic Auth, Bearer Token, or API Key authentication methods and enter your credentials.

3

Select target language

Pick your desired output language — JavaScript fetch, axios, Python requests, cURL, Go, or Rust.

4

Copy the generated code

Click the Copy button to copy the ready-to-use code snippet directly to your clipboard.

Examples

Practical examples to help you get the most out of Request Builder:

POST request generated as fetch

fetch('https://api.example.com/data', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'Bearer eyJhbGciOiJIUzI1NiIs...'
  },
  body: JSON.stringify({
    name: 'John Doe',
    email: 'john@example.com'
  })
})

POST request generated as Python requests

import requests

url = 'https://api.example.com/data'
headers = {
    'Content-Type': 'application/json',
    'Authorization': 'Bearer eyJhbGciOiJIUzI1NiIs...'
}
data = {
    'name': 'John Doe',
    'email': 'john@example.com'
}
response = requests.post(url, headers=headers, json=data)

Common Mistakes and How to Avoid Them

Missing Content-Type header for requests with a body

When sending POST, PUT, or PATCH requests with a JSON body, always include Content-Type: application/json. Without it, the server may not parse the body correctly.

Not stringifying the body in JavaScript fetch

The fetch API requires the body to be a string for JSON payloads. Use JSON.stringify() to convert your JavaScript object before passing it as the body parameter.

Frequently Asked Questions

What languages can I generate code for?

JavaScript (fetch, axios), Python (requests), cURL, Go, and Rust are currently supported. More languages are planned.

Can I set custom headers and auth?

Yes. Add custom headers, query parameters, and request body. Auth options include Basic Auth, Bearer Token, and API Key headers.

How does the visual builder work?

Fill in the URL, select the HTTP method, add headers and body using form fields. The tool generates ready-to-use code snippets in your chosen language.

Is my request data sent to a server?

No. All request building and code generation happens locally in your browser.

Key Features

Visual Builder

Build requests with form fields for URL, method, headers, body, and params.

Multi-Language

Generate code for fetch, axios, curl, Python requests, and more.

Auth Support

Basic auth, Bearer token, API key header generation.

One-Click Copy

Copy generated code snippets directly to clipboard.

Common Use Cases

Request Builder is useful in a variety of scenarios across different workflows:

Generate fetch or axios code snippets for quick integration into web apps

Build authenticated API requests with Bearer tokens or API keys

Convert visual request configurations into production-ready code

Tips & Best Practices

Generate language-specific code

Use the multi-language export to generate code in JavaScript, Python, Go, and Rust — perfect for teams using different stacks.

Test auth headers visually

Build requests with different auth types (Basic, Bearer, API Key) visually before committing to code implementation.

More Tools in This Workspace

Explore more tools in the API workspace:

REST API Client

Send HTTP requests (GET, POST, PUT, DELETE) and inspect responses from your browser.

WebSocket Tester

Connect to WebSocket endpoints, send messages, and inspect frames.

HTTP Status Code Reference

Searchable reference of all HTTP status codes with descriptions and use cases.

curl to Fetch Converter

Convert curl commands to JavaScript fetch, Python requests, and more.

OpenAPI Validator

Validate OpenAPI 3.x and Swagger 2.0 specifications for correctness.

Mock API Generator

Generate mock API responses from JSON schemas for rapid development.