n8n HTTP Request JSON Builder

Build headers, a typed JSON body and a cURL preview for n8n's HTTP Request node. Everything you type stays in this browser; only an anonymous “tool used” event is counted.

Method URL

Headers — one key=value per line JSON body — one key=value per line

Values like true, false, null and numbers are typed automatically. Dot notation such as profile.age=18 creates nested JSON.

Headers JSON

{}

Body JSON

{}

cURL preview

Build a request to generate cURL.

Use this in n8n

Add an HTTP Request node and choose the generated method.
Paste the URL.
If you have headers, enable header parameters and use the generated values.
For POST/PUT/PATCH, enable the request body and choose JSON, then use the generated body object.
Keep credentials in n8n Credentials when possible rather than hard-coding long-lived secrets.

n8n's HTTP Request node is intended for calling APIs when a dedicated app action is unavailable. Verify the target API's authentication and body requirements.

Why this exists

Most HTTP Request setup errors come from malformed JSON, wrong value types, missing headers, or a mismatch between the request body and the API. This builder turns simple key/value lines into valid JSON while showing the equivalent cURL request for debugging.

Examples

Flat JSON: name=Alice and active=true become {"name":"Alice","active":true}.

Nested JSON: customer.email=a@example.com becomes {"customer":{"email":"a@example.com"}}.

Fix “JSON parameter needs to be valid JSON” · Fix 401 / Bearer / API key auth · n8n HTTP Request examples

More free tools · AI API Cost Calculator · Product Image Checker