How to manually send HTTP POST requests from Firefox or Chrome browser

CURL is awesome to do what you want! It's a simple, but effective, command line tool.

REST implementation test commands:

curl -i -X GET http://rest-api.io/items curl -i -X GET http://rest-api.io/items/5069b47aa892630aae059584 curl -i -X DELETE http://rest-api.io/items/5069b47aa892630aae059584 curl -i -X POST -H 'Content-Type: application/json' -d '{"name": "New item", "year": "2009"}' http://rest-api.io/items curl -i -X PUT -H 'Content-Type: application/json' -d '{"name": "Updated item", "year": "2010"}' http://rest-api.io/items/5069b47aa892630aae059584 

Firefox

Open Network panel in Developer Tools by pressing Ctrl+Shift+E or by going Menubar -> Tools -> Web Developer -> Network. Select a row corresponding to a request.

Newer versions

Look for a resend button in the far right. Then a new editing form would open in the left. Edit it.

Older versions

Then Click on small door icon on top-right (in expanded form in the screenshot, you'll find it just left of the highlighted Headers), second row (if you don't see it then reload the page) -> Edit and resend whatever request you want

Forget the browser and try CLI. HTTPie is a great tool!

CLI HTTP clients:

• HTTPie
• Curlie
• HTTP Prompt
• Curl
• wget

If you insist on a browser extension then:

Web clients

• Insomnia
• Hoppscotch
• To avoid: Postman is insecure: Postman Carries Lots of Secrets

VS Code

• Thunder client

Browser extension:

• Talend API Tester - Free Edition

Having been greatly inspired by Postman for Chrome, I decided to write something similar for Firefox.

REST Easy* is a restartless Firefox add-on that aims to provide as much control as possible over requests. The add-on is still in an experimental state (it hasn't even been reviewed by Mozilla yet) but development is progressing nicely.

The project is open source, so if anyone feels compelled to help with development, that would be awesome: https://github.com/nathan-osman/Rest-Easy

_{* the add-on available from http://addons.mozilla.org will always be slightly behind the code available on GitHub}

I think that Benny Neugebauer's comment on the OP question about the Fetch API should be presented here as an answer since the OP was looking for a functionality in Chrome to manually create HTTP POST requests and that is exactly what the fetch command does.

There is a nice simple example of the Fetch API here:

// Make sure you run it from the domain 'https://jsonplaceholder.typicode.com/'. (cross-origin-policy) fetch('https://jsonplaceholder.typicode.com/posts',{method: 'POST', headers: {'test': 'TestPost'} }) .then(response => response.json()) .then(json => console.log(json)) 

Some of the advantages of the fetch command are really precious: It's simple, short, fast, available and even as a console command it stored on your chrome console and can be used later.

The simplicity of pressing F12, write the command in the console tab (or press the up key if you used it before) then press Enter, see it pending and returning the response is what making it really useful for simple POST requests tests.

Of course, the main disadvantage here is that, unlike Postman, this won't pass the cross-origin-policy, but still I find it very useful for testing in local environment or other environments where I can enable CORS manually.

You specifically asked for "extension or functionality in Chrome and/or Firefox", which the answers you have already received provide, but I do like the simplicity of oezi's answer to the closed question "How can I send a POST request with a web browser?" for simple parameters. oezi says:

With a form, just set method to "post"

<form action="blah.php" method="post"> <input type="text" name="data" value="mydata" /> <input type="submit" /> </form> 

I.e., build yourself a very simple page to test the POST actions.

Here's the Advanced REST Client extension for Chrome.

It works great for me -- do remember that you can still use the debugger with it. The Network pane is particularly useful; it'll give you rendered JSON objects and error pages.

For Firefox there is also an extension called RESTClient which is quite nice:

RESTClient, a debugger for RESTful web services

It may not be directly related to browsers, but Fiddler is another good software.

There have been some other clients born since the rise of Postman that is worth mentioning here:

• Insomnia: with both desktop application and Chrome plugin
• Hoppscotch: previously known as Postwoman, and with a Chrome plugin available as well. You can also make it work locally with docker if you want to get funny
• Paw: if you are on Mac
• Advanced Rest Client: already mentioned as a Chrome plugin, but it is worth pointing out that it also has a desktop application
• soapUI: written in Java and with lots of testing functionality
• Boomerang: yet another way to test APIs. It comes with SOAP integration and it also has a Chrome plugin available
• Thunder Client: if you use VS Code as your text editor then you should go and check out this awesome extension

The question being 12 years old now, it is easy to understand why the author asked a solution for Firefox or Chrome back then. After 12 years though, there are also other browsers and the best one which does not involve any add-ons or additional tools is Microsoft Edge.

Just open devtools (F12) and then Network Console tab (not the Network or Console tab. Click on + sign and open it, if it is not visible.).

And here is the official guide: https://learn.microsoft.com/en-us/microsoft-edge/devtools-guide-chromium/network-console/network-console-tool

Have fun!

You could also use Watir or WatiN to automate browsers. Watir is written for Ruby and Watin is for .NET languages. I am not sure if it's what you are looking for, though.

• http://watin.sourceforge.net/
• http://watir.com/

Try Runscope. A free tool sampling their service is provided at https://www.hurl.it/.

You can set the method, authentication, headers, parameters, and body. The response shows status code, headers, and body. The response body can be formatted from JSON with a collapsable hierarchy.

Paid accounts can automate test API calls and use return data to build new test calls.

COI disclosure: I have no relationship to Runscope.

Check out http-tool for Firefox...

Aimed at web developers who need to debug HTTP requests and responses. Can be extremely useful while developing REST based API.

Features:

• GET
• HEAD
• POST
• PUT
• DELETE

Add header(s) to request.
Add body content to request.

View header(s) in response.
View body content in response.
View status code of response.
View status text of response.

You can post requests directly from the browser with ReqBin. No plugin or desktop application is required.

I tried to use postman app, had some auth issues. If you have to do it exclusively using browser, go to network tab, right click on the call, say edit and send response. There is a similar ans on here about Firefox, this right click worked for me on edge and pretty sure it would work for chrome too

So it occurs to me that you can use the console, create a function, and just easily send requests from the console, which will have the correct cookies, etc.

so I just grabbed this from here: https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch#supplying_request_options

// Example POST method implementation: async function postData(url = '', data = {}, options = {}) { // Default options are marked with * let defaultOptions = { method: 'POST', // *GET, POST, PUT, DELETE, etc. mode: 'cors', // no-cors, *cors, same-origin cache: 'no-cache', // *default, no-cache, reload, force-cache, only-if-cached credentials: 'same-origin', // include, *same-origin, omit headers: { 'Content-Type': 'application/json' // 'Content-Type': 'application/x-www-form-urlencoded', }, redirect: 'follow', // manual, *follow, error referrerPolicy: 'no-referrer', // no-referrer, *no-referrer-when-downgrade, origin, origin-when-cross-origin, same-origin, strict-origin, strict-origin-when-cross-origin, unsafe-url body: JSON.stringify(data) // body data type must match "Content-Type" header } // update the default options with specific options (e.g. { "method": "GET" } ) const requestParams = Object.assign(defaultOptions, options); const response = await fetch(url, requestParams); return response.text(); // displays the simplest form of the output in the console. Maybe changed to response.json() if you wish } 

IF YOU WANT TO MAKE GET REQUESTS, you can just put them in your browser address bar!

if you paste that into your console, then you can make POST requests by repeatedly calling your function like this:

postData('https://example.com/answer', { answer: 42 }) .then(data => { console.log(data); // you might want to use JSON.parse on this }); 

and the server output will be printed in the console (as well as all the data available in the network tab)

This function assumes you are sending JSON data. If you are not, you will need to change it to suite your needs

Windows CLI solution

In PowerShell you can use Invoke-WebRequest. Example syntax:

Invoke-WebRequest -Uri http://localhost:3000 -Method POST -Body @{ username='clever_name', password='hunter2' } -UseBasicParsing 

On systems without Internet Explorer, you need the -UseBasicParsing flag.

we can not do POST requests the same way we do the GET requests as GET requests can be done directly by typing a URL into Chrome's address bar, POST requests require a body and more control — so they can't be done that way. But we still can send manual POST requests in Chrome using the fetch API in the browser console.

fetch("https://example.com/api/data", { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify({ name: "john", id: 2 }) }) .then(res => res.json()) .then(data => console.log(data));