cURL to Fetch Converter

API documentation, developer blogs, and command-line tutorials overwhelmingly provide code samples as raw cURL commands. Translating cURL requests into modern JavaScript fetch() syntax manually requires parsing HTTP methods, splitting headers, parsing query parameters, and serializing JSON payloads.

Manual conversion is tedious and prone to syntax bugs such as misquoted quotation marks, forgotten CORS headers, or incorrect Content-Type declarations.

This in-browser cURL to Fetch converter parses shell cURL commands and translates them instantly into clean, idiomatic JavaScript async/await fetch() syntax. It formats options objects, headers, and request bodies cleanly.

To implement HTTP client requests, inspect server headers with the HTTP headers inspector and format request payloads using the JSON formatter.

Step-by-step practical guide

1. Paste your cURL command into the input editor box.
2. Select your output style preference: Modern async/await syntax or Promise .then() chain syntax.
3. Toggle the Include Error Handling toggle to generate try/catch block templates automatically.
4. Click Convert to Fetch to parse the cURL command line arguments.
5. Inspect the generated JavaScript code in the syntax-highlighted editor.
6. Click Copy Code to transfer the ready-to-use fetch function directly into your frontend or Node.js codebase.

Engineering specifications and execution details

Parses cURL command flags including -X (HTTP method), -H (headers), -d and --data (request bodies), -u (basic auth), and -k (insecure flags).

Detects JSON payload strings and serializes body properties using JSON.stringify() where appropriate.

Handles multi-line shell commands containing trailing backslashes (\) and Unix line continuations.

Formats code output adhering to modern ES2022 asynchronous JavaScript standards.

Operates completely inside local browser memory with zero external network transmission.

Data privacy and memory isolation

Your private API secret keys, authorization bearer tokens, and internal microservice URLs remain strictly on your computer.

No API credentials are logged or saved to any server.

Common production use cases

• Frontend developers migrating cURL examples from Stripe, Twilio, or GitHub API documentation into React or Vue applications.
• Node.js engineers building server-side microservice calls from terminal cURL prototypes.
• QA engineers translating postman or command-line API calls into automated browser test scripts.
• Students and junior engineers learning modern JavaScript fetch() networking patterns.
• Technical writers converting developer documentation snippets into web-friendly examples.

Edge cases and operational boundaries

• Basic authentication: Flags like -u username:password are converted into standard Authorization: Basic base64 encoded headers.
• Form urlencoded bodies: cURL -d "param1=val&param2=val" commands are parsed into URLSearchParams payloads.
• Trailing slashes in URLs: Path formatting and query strings are preserved accurately without unexpected truncation.
• Cookies in cURL: The -b or --cookie flags are mapped to Cookie request headers where applicable.