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cURL to Fetch Converter

Convert cURL commands to JavaScript Fetch API, Axios, and other HTTP client code formats.

Tested tool guide Tested browser tools Checked August 16, 2026

What cURL to Fetch Converter does and how it behaves

Paste a cURL command to turn its request description into JavaScript Fetch API, Axios, or another output format offered by the converter. It maps the command's target URL, HTTP method, headers, and body into corresponding source-code fields. The result is code to review and run, not evidence that the server accepted the request. The main surprise is environmental: a request that works in curl can fail in browser Fetch because the browser applies cross-origin rules, manages some headers and credentials, and does not expose every curl capability. Conversion stays in the browser, which is relevant when the command contains secrets.

How the result is produced

1

Request mapping

For a conventional single-request command, the URL becomes the request target. An explicit -X or --request value identifies the HTTP method, -H or --header values supply headers, and data options supply the body. Shell quoting around those values must become valid string quoting for the chosen code format. If the command relies on shell evaluation, the visible text may not fully describe the final request.

2

Target-specific syntax

Selecting Fetch, Axios, or another supported target changes the syntax used to represent the same request fields. Fetch places method, headers, and body in a request options object passed with the URL. Axios represents them with its own request call and configuration fields. The converter can preserve explicit values, but it cannot infer whether an unlabeled body is JSON, URL-encoded form data, or plain text.

Good uses

  • Convert a cURL example from an API provider's documentation into Fetch code for a browser prototype.
  • Rewrite a request copied as cURL from developer tools into Axios code for an existing JavaScript project.
  • Audit a migration by comparing the original cURL method, headers, and payload with the fields in generated client code.

Limits and checks

  • Generated Fetch code cannot bypass CORS. The server must permit the browser origin and requested method or headers when cross-origin authorization is required.
  • Some curl behavior has no browser Fetch equivalent, including proxy selection, custom DNS resolution, and disabling TLS certificate verification. Do not assume such flags are represented.
  • Shell variables, command substitution, pipes, and file-backed arguments such as @payload.json are not self-contained values. The converter cannot recover runtime text or unpasted file contents.

Common questions

Will the generated Fetch code behave exactly like curl?

No. The converter can represent core HTTP request details, but curl is a command-line client and browser Fetch is governed by browser security and networking behavior. Cross-origin permission, forbidden or automatically managed headers, cookie policy, redirects, client certificates, proxy selection, and TLS options can differ. Treat the output as translated request code, then test it in the environment where it will run.

Does the converter send my request or upload the command?

No. It converts the pasted command into source code; it does not send the request or prove what response the endpoint will return. The conversion takes place in the browser, and nothing is uploaded. Generated code can still contain bearer tokens, Basic authentication, cookies, API keys, or signed query parameters, so redact secrets before saving, sharing, or committing it.

References and verification

The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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