What this cURL converter does

Many API documentation pages show examples as cURL commands because cURL is compact, widely available and easy to copy into a terminal. That is useful for testing, but it does not directly answer the next question: how do you write the same request inside a JavaScript app, PHP script or WordPress plugin? This tool bridges that gap. Paste a common cURL command and it extracts the method, URL, headers, body, form fields, basic auth, cookies and warning flags. Then it generates JavaScript fetch, PHP cURL and WordPress HTTP API code.

The converter is designed for practical API documentation patterns, not every possible shell trick. It handles common flags such as -X, --request, -H, --header, -d, --data, --data-raw, -F, --form, -u, --user, -b, --cookie, -I, --head, -L and -k. It also warns about things that should be reviewed manually, such as file uploads, insecure SSL flags, cookies, binary data and secrets in headers.

This tool does not send the request. It does not test whether the API works. It does not validate credentials. It simply converts a pasted command into code starting points. After copying the output, you should still review API documentation, environment variables, secret storage, error handling, CORS behavior and server-side security before using the code in production.

Why convert cURL into JavaScript, PHP or WordPress code?

cURL is great for quick tests because it represents an HTTP request in one command. A command can include the URL, method, headers, body, credentials and extra flags. But applications usually need structured code. A browser app needs fetch or another JavaScript HTTP client. A PHP backend might use PHP’s cURL extension. A WordPress plugin or theme should usually use WordPress’s HTTP API functions, because they integrate with WordPress conventions, filters and error handling.

For example, a cURL command with -H "Content-Type: application/json" and -d data means the generated code should include a JSON body and the right content type header. A command with -X PATCH needs a custom method. A command with Authorization: Bearer needs a secure place for the token. A command with --user means the original used basic authentication, which should be handled carefully. This tool makes those pieces easier to see.

If your request URL contains query parameters, use the CodeZips Query String Parser and Builder to inspect them before converting. If the URL contains encoded values, redirect URLs or special characters, the CodeZips URL Encoder and Decoder can help you understand the final URL. If the request body is JSON and you want to inspect it separately, use the CodeZips JSON Formatter and Validator.

What parts of cURL are converted?

Some shell features are intentionally not fully interpreted. Environment variables, file references, command substitution, process substitution and complex quoting can mean different things depending on shell and operating system. Treat generated code as a strong starting point, then review the request carefully.

Example: cURL to JavaScript fetch

A typical API documentation example might look like this:

curl -X POST https://api.example.com/v1/customers \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"name":"Sagar","plan":"pro"}'

The equivalent JavaScript fetch request needs a URL, method, headers and body. If the body is JSON, the body should usually be a JSON string. The generated code also includes response handling so you can inspect non-2xx status codes instead of assuming every response is successful.

const response = await fetch("https://api.example.com/v1/customers", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_TOKEN",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "name": "Sagar",
    "plan": "pro"
  })
});

const data = await response.json();

Browser fetch has one important limitation that cURL does not have: CORS. A request can work in terminal cURL but fail in a browser if the API does not allow your site origin. If a request works in Postman or terminal but fails in the frontend, check the browser Network tab, preflight request, allowed headers, credentials mode and server CORS configuration.

Example: cURL to WordPress HTTP API

When you are inside WordPress, it is usually better to use WordPress HTTP API functions instead of raw PHP cURL in theme or plugin code. WordPress provides functions such as wp_remote_get, wp_remote_post and wp_remote_request. These functions return arrays or WP_Error objects, so good code should check for errors before reading the response body.

$response = wp_remote_request( 'https://api.example.com/v1/customers', array(
    'method'  => 'POST',
    'timeout' => 20,
    'headers' => array(
        'Authorization' => 'Bearer YOUR_TOKEN',
        'Content-Type'  => 'application/json',
    ),
    'body'    => wp_json_encode( array(
        'name' => 'Sagar',
        'plan' => 'pro',
    ) ),
) );

if ( is_wp_error( $response ) ) {
    return $response->get_error_message();
}

$body = wp_remote_retrieve_body( $response );

For WordPress, token storage matters. Do not hard-code private API keys in a public theme file. Use environment configuration, plugin settings with proper capability checks, server-side storage, or other secure handling appropriate for your project. Also remember that a browser-side request and a WordPress server-side request can behave differently because they come from different origins and IP addresses.

Common mistakes when converting cURL

Forgetting that -d usually implies POST

Many cURL examples do not explicitly include -X POST. If the command includes data with -d, cURL commonly sends a POST-style request. When converting into code, the method should not accidentally remain GET if a body is present.

Copying secrets directly into frontend JavaScript

Bearer tokens, private API keys, basic auth passwords and secret cookies should not be placed in browser JavaScript if they are meant to be private. Browser code can be inspected by users. For private APIs, call the API from a backend or WordPress server-side function instead.

Treating every body as JSON

Some requests send JSON, but others send form data, URL-encoded data, multipart upload fields or raw text. The content type header and cURL flags matter. If the request uses -F, file upload conversion usually needs manual review instead of a simple JSON body.

Ignoring response status checks

A generated request is only half the code. Real applications need to handle error responses. A fetch request does not automatically throw for every HTTP error status. PHP cURL needs response status inspection. WordPress HTTP API returns WP_Error for transport-level failures, but API-level errors may still come back as normal HTTP responses.

Assuming terminal behavior equals browser behavior

cURL can send requests from your machine without browser CORS restrictions. Browser fetch must follow browser security rules. If a request works in cURL but not in the browser, do not assume the generated JavaScript is wrong. Check CORS, preflight, allowed headers, credentials and whether the API is meant to be called from frontend code.

Debugging converted API requests

After conversion, test with a safe endpoint or sandbox account first. Confirm the method, URL, headers and body match the original cURL command. If the request fails, capture the status code, response body and response headers. If the body is JSON, format it with the CodeZips JSON Formatter and Validator so you can read field-level errors. If the URL contains many parameters, inspect them with the CodeZips Query String Parser and Builder.

Authentication problems often involve tokens, encoded values and timestamps. If the request uses a JWT, the CodeZips JWT Decoder can help inspect non-secret claims such as expiry and issuer. If a token or state value uses URL-safe Base64, the CodeZips Base64 URL-Safe Encoder and Decoder may help you understand the encoding. If an API response gives a Unix timestamp for token expiry or rate-limit reset, use the CodeZips Unix Timestamp Converter.

If you are publishing the converted code in a WordPress article, make sure the examples display correctly. Raw code examples with angle brackets, ampersands or script tags can render incorrectly if they are not escaped. The CodeZips HTML Entity Encoder and Decoder can help display code examples safely inside posts and documentation.

When to use this tool vs related CodeZips tools

Final practical note

cURL is a great testing language, but application code needs context. A good conversion should preserve the method, URL, headers and body while also adding safe error handling and secret management. Use this tool to create a strong first draft, then compare the output with the API documentation, test in a safe environment and move private credentials out of public code.