--- url: https://findutils.com/guides/http-request-builder-guide title: "HTTP Request Builder: Send Public HTTP Calls Safely" description: "Build and send a public HTTP request. Read status, headers, and body. Private, local, and metadata hosts are rejected. The timeout is 15 seconds." category: developer content_type: guide locale: en read_time: 5 status: published author: "codewitholgun" published_at: 2026-08-27T08:20:00Z updated_at: 2026-08-27T08:20:00Z excerpt: "Set method, URL, headers, and body, then send to a public http or https host. Localhost and private ranges are blocked. Body limit is 64 KB." tag_ids: ["developer-tools", "http", "api", "request-builder", "curl"] tags: ["Developer Tools", "HTTP", "API", "Request Builder", "cURL"] primary_keyword: "HTTP request builder" secondary_keywords: ["http client online", "send http request in browser", "api request tester", "public http request tool", "http request builder free"] tool_tag: "http-request-builder" related_tool: "http-request-builder" related_tools: ["http-request-builder", "har-viewer", "curl-to-code", "http-status-code-lookup"] og_image: "/images/content/guides/http-request-builder-response.webp" image_alt: "An HTTP method chip, URL capsule, and header rows on the left face a response card, with private hosts blocked at a filter." --- An HTTP request builder lets you set method, URL, headers, and body, then read status, headers, and body from the response. Open the FindUtils [HTTP Request Builder](/developers/http-request-builder/) to send a request to a public `http` or `https` host. Private, local, and metadata addresses are rejected. The abort timeout is 15 seconds. The request body limit is 64 KB. Only `http://` and `https://` URLs are allowed. `javascript:`, `data:`, and `file:` are rejected. ## Why Use a Request Builder A builder is faster than writing a one-off script when you need to see a status line. It is also safer than a wide-open proxy, because private and loopback hosts are blocked. Use this builder when: - **You need a public API status quickly.** Send GET or POST and read the body. - **You copied a request from a HAR or cURL.** Replay it against a public host. - **You must not hit localhost.** The builder rejects loopback, private ranges, and metadata addresses. - **You want typed headers only.** The browser call to FindUtils uses `credentials: omit`. Only headers you type are sent to the destination. The honest limit: this is not a full desktop API client. It will not open `http://127.0.0.1`, it will not send findutils.com cookies, and it stops after 15 seconds. ## How to Send a Request Choose a method. Enter a public URL. Add headers and a body only when the server needs them. ### Step 1: Set method and URL Open the FindUtils [HTTP Request Builder](/developers/http-request-builder/). Choose GET, POST, PUT, PATCH, DELETE, HEAD, or OPTIONS. Enter a public `http` or `https` URL. ### Step 2: Add headers and body Optional. Set `Content-Type` yourself if the server needs it. The default sample header is `Accept: application/json`. Keep the body under 64 KB. ### Step 3: Send Click Send. After 15 seconds the request stops. ### Step 4: Read the result The panel shows status, headers, and body. Look up an unfamiliar status on the [HTTP Status Code Lookup](/network/http-status-code-lookup/) tool. ## HTTP Request Builder vs cURL vs a Desktop Client Each surface has a different trust and reach model. | Feature | FindUtils HTTP Request Builder | cURL on your machine | Desktop API client | |---------|--------------------------------|----------------------|--------------------| | Price | Free, no signup | Free | Free tier or paid | | Public http/https | Yes | Yes | Yes | | Localhost / private ranges | Rejected | Allowed | Usually allowed | | Timeout | 15 seconds | You choose | You choose | | Body limit | 64 KB | Large | Large | | Sends FindUtils cookies | No | Not applicable | Not applicable | | Signup | No | No | Often yes | **Best for:** Use FindUtils for a short call to a public host. Use cURL or a desktop client for localhost, private APIs, large bodies, or long-running requests. If you already have a command, convert it with [cURL to Code](/developers/curl-to-code/). If you have a DevTools export, inspect it in the [HAR Viewer](/developers/har-viewer/) first. ## Practical Examples ### Example 1: Check a public JSON endpoint Method GET. URL `https://example.com/`. Header `Accept: application/json`. Read status and body. ### Example 2: Replay a public POST from a HAR row Parse the HAR. Copy cURL. Recreate method, URL, headers, and body in the builder. Send only if the host is public. ### Example 3: Confirm a blocked local URL Enter `http://127.0.0.1:3000/`. The builder rejects it. That is the intended safeguard, not a bug. ## Common Mistakes ### Mistake 1: Pointing the builder at localhost Localhost, private ranges, and metadata addresses are rejected. Use cURL on your own machine for local servers. ### Mistake 2: Omitting Content-Type on JSON POST The builder does not guess. Add `Content-Type: application/json` when the server expects JSON. ### Mistake 3: Sending a body over 64 KB The request fails with a body-too-large error. Trim the payload or use cURL. ### Mistake 4: Waiting through a hung host The timeout is 15 seconds. A host that never answers fails with the timeout message. ## Limits You Should Plan For The builder sends only to public `http` and `https` hosts. That rule is the product. It is not a temporary CORS workaround. The timeout is 15 seconds. The body cap is 64 KB. Too many requests in a short window return a rate-limit error. Wait a minute and try again. The browser call to FindUtils uses `credentials: omit`. FindUtils cookies are not forwarded. Only headers you type go to the destination. This page is not a substitute for cURL against localhost or a VPN-only API. ## Tools Used in This Guide - **[HTTP Request Builder](/developers/http-request-builder/)** — Send a public HTTP request and read the response - **[HAR Viewer](/developers/har-viewer/)** — Inspect a DevTools HAR and copy cURL - **[cURL to Code](/developers/curl-to-code/)** — Convert a cURL command into code - **[HTTP Status Code Lookup](/network/http-status-code-lookup/)** — Explain a status code ## FAQ **Q: Is the HTTP request builder free?** A: Yes. FindUtils HTTP Request Builder is free, with no signup. **Q: Which URLs are allowed?** A: Public `http` and `https` hosts. Localhost, private ranges, and metadata addresses are rejected. **Q: Can I hit localhost?** A: No. Localhost, private ranges, and metadata addresses are rejected. **Q: Is there a timeout?** A: Yes. 15 seconds. **Q: Are findutils.com cookies sent?** A: No. The browser call to FindUtils uses credentials omit. Only headers you type are sent to the destination. **Q: Why might a public site fail?** A: The host may be down, DNS or TLS may fail, the body may be too large, or you may hit the rate limit. **Q: Do I need an account?** A: No. Set the fields and click Send. ## Next Steps - Inspect captured traffic with the [HAR Viewer](/developers/har-viewer/) - Convert a working command with [cURL to Code](/developers/curl-to-code/) - Read the [HAR viewer guide](/guides/har-viewer-guide/) - Look up codes with [HTTP Status Code Lookup](/network/http-status-code-lookup/)