How to modify HTTP(s) Request & Response Headers in Chrome, Firefox & Safari using Requestly

HTTP(s) Headers are key-value pairs that can be used by the client or the server to pass additional information along with an HTTP(s) request or response. An HTTP(s) header consists of its case-insensitive name followed by a colon (:), then by its value.

The ability to modify the headers of traffic that passes through your browser is a great tool to have.

You can delete certain headers to minimize online tracking, remove CSP while testing, test sites in production and so on.

Using Requestly, Headers can be added/modified by a simple series of clicks. All you need is to install Requestly extension in your browser.

Modify HTTP Headers could be selected from the options of different rules on the left side of your screen.

Select if you want to modify request header or response header and give a suitable name and description to the rule.

Remove Content-Security-Policy Response Header (Example)

Step 1. Select Header Type — Request Headers or Response Headers

Step 2. Select Operation — Add/Remove/Modify

You can add a new header or remove, modify an existing request/response header. For this example, we will select Remove.

Difference between Add and Modify option

Add operation works when a new header is to be added to the request/response whereas modify option modifies an already existing header.

Step 3. URL Targeting — Specify when Modify Headers rule should apply

You can apply the rules based on URL, hostname or path. You can also use regex to match it.

More Examples

If you haven’t installed Requestly yet, please install it to modify request and response headers. Reach out to for any questions.

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