cURL to Fetch Converter

Convert any cURL request into clean JavaScript fetch code.

cURL to Fetch Converter

Convert a cURL command into copy-ready JavaScript fetch code.

Settings Prefilled examples
TypeScript mode uses typed declarations where it helps readability.
Adds credentials: "include" to the fetch options.
Result Copy-ready
No output yet
Paste a cURL command and click Generate.
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About cURL to Fetch Converter

cURL to Fetch Converter – Convert cURL commands to JavaScript Fetch

If you have an API request captured as a cURL command, this tool converts it into clean JavaScript fetch() code you can paste into a browser app, Node.js script, or frontend project. It focuses on the parts developers actually need—URL, HTTP method, headers, and request body—while keeping the output readable and easy to tweak. Use it to speed up debugging, build quick repros, or translate terminal snippets into client-side code.

How cURL to Fetch Converter Works

The converter reads a cURL command and extracts the request components that matter for an equivalent fetch() call. It identifies the URL, method, headers, and body payload, then prints a structured options object and a response handling snippet. For common cases (JSON APIs, form-encoded payloads, plain text bodies), the generated fetch is ready to run with minimal edits.

Step-by-Step

  • 1) Paste your cURL: Provide a full cURL command copied from a terminal, browser DevTools, or API docs.
  • 2) Parse request details: The tool detects flags like -X/--request, -H/--header, and -d/--data* to rebuild the request.
  • 3) Build a fetch options object: It maps the method, headers, and body into the correct fetch(url, options) structure.
  • 4) Choose output style: Switch between JavaScript or TypeScript-friendly output, and optionally include credentials handling.
  • 5) Copy or download: Copy the generated code to your clipboard or download it as a text file for later use.

Key Features

Accurate method and URL mapping

The converter translates explicit cURL methods (for example -X POST) and infers methods when a body is present. It also supports commands that pass the URL via --url or as the last argument.

Header extraction with sensible formatting

Headers supplied through repeated -H flags are collected into a single headers object. The output preserves header names and values, so authentication tokens, content types, and custom headers remain intact.

Body handling for common API payloads

Data flags such as -d, --data-raw, and --data-binary are converted into a fetch body. If a JSON content type is detected, the tool can emit JSON.stringify() output; for form-encoded payloads it can emit URLSearchParams.

Options for credentials and response parsing

Many APIs rely on cookies or cross-site credentials. You can opt in to credentials: 'include' and generate a response snippet that safely reads JSON when available, falling back to text when needed.

Copy, download, and iterate quickly

The UI is designed for fast iteration: paste, generate, copy, run, and adjust. It’s especially useful when you’re debugging an endpoint and want to compare behavior between cURL and the browser.

Use Cases

  • Frontend integration: Convert API documentation cURL examples into fetch calls for React, Vue, or vanilla apps.
  • Bug reproduction: Turn a failing terminal command into a browser-based repro that teammates can run quickly.
  • Testing and QA: Generate a fetch snippet that can be dropped into a small test harness or mocked environment.
  • API debugging: Compare headers, payload, and method details between your app and a known-good cURL request.
  • Learning and onboarding: Help new developers understand how cURL flags map to fetch options.
  • Node.js scripts: Produce fetch code that works with modern Node runtimes, then expand it into retries, logging, or pagination.

Whether you are copying examples from API docs or exporting a request from DevTools, converting to fetch reduces friction and helps you move from “command” to “code” in seconds.

Optimization Tips

Verify the Content-Type

If your cURL includes a Content-Type header, keep it consistent with the body you send. For JSON APIs, use application/json and ensure the generated body is valid JSON. For form submissions, prefer application/x-www-form-urlencoded or multipart/form-data depending on the endpoint.

Handle auth securely

Converted requests may include tokens (for example Authorization: Bearer …). Treat generated code like a secret and avoid committing credentials to source control. Consider moving tokens into environment variables or secure secrets management.

Adjust response parsing

Not every endpoint returns JSON. If an API responds with plain text, HTML, or a file download, switch the response handler to response.text() or response.blob(). The generated snippet is a starting point—tailor it to your endpoint’s response type.

FAQ

Yes. You can paste multi-line cURL commands (with backslashes) and the tool will normalize whitespace and parse common flags. If your command uses rare flags, you can still use the output as a base and adjust it manually.

Fetch handles cookies via the credentials option and browser cookie policy. If you need cookie-based auth, enable credentials in the tool and ensure your server allows it with the right CORS headers.

Multipart uploads can vary a lot. The converter will capture the fields it can and emit guidance-friendly output. For file uploads, you may need to create a FormData object and append a File or stream manually.

The output is standard fetch syntax. Modern Node.js versions include fetch by default; older versions may require a polyfill. In browsers, it runs as-is (subject to CORS rules).

Yes. Choose the TypeScript output option to get typed variables and a slightly more explicit structure. You can still customize the types based on your API’s response schema.

Why Choose cURL to Fetch Converter?

This tool bridges two common workflows: capturing HTTP requests with cURL and implementing them in JavaScript applications. Instead of manually rewriting flags into a fetch options object, you get a clean, editable snippet that reflects the original request accurately.

Because the generated code is readable and standards-based, it fits into real projects—quick prototypes, production debugging, documentation examples, and automated tests. Paste your command, generate the fetch call, and keep moving.