Inserting scripts dynamically in a webpage
Inject popular libraries or hosted scripts or execute custom code-snippet before or after page load using simple rule builder.
Customize any Webpage using Requestly's Insert script Rule. Add Custom JavaScript (JS) or Styles (CSS) Remove/hide unwanted sections, add action buttons, add your own libraries to support your script, etc.‍
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Happy Users
Download for Chrome
Download for other platforms/browsers
Inject JS Script
 Inject CSS
Multiple Scripts Support
Here's how you can use Requestly's Insert Custom Scripts feature in your daily workflow
Download for Chrome
Download for other platforms/browsers
Explore real workflows that save companies time, eliminate old tools, and bring peace of mind.
Inject popular libraries or hosted scripts or execute custom code-snippet before or after page load using simple rule builder.
A complete HTTP debugging software that works in your browser, simple & fast.
Redirect a request URL (or matching pattern) to another URL.
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Test edge cases in your app by simulating API responses‍
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Add, delete, override request & response headers
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Check how your site looks on multiple devices, browsers, dimensions etc
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Edit Content-Type, Status Code, and Body of the Response on our Server.
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Block requests, websites by specifying keywords or entire URL.
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Delay requests by specifying keywords or entire URL.
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4.7/5 Star ratings
1000+ Chrome web store reviews
Happy Users
Luke Seleenbinder
Founder & CEO - Stadia Maps
When I think about Requestly, I think it fits one of the key aspects of selling a product - show rather than tell. Requestly gives us the power to show the customers our solution on their own websites rather than some demo environment which they're not familiar with.
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Robert Thelen
Co-founder & CEO
Requestly has eliminated the complexity of testing environments for us, allowing our development team to directly test API and JS snippet changes on customer apps and sites without the need for deployment cycles.
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Afsheen Amroliwala
Software Development Engineer
With Requestly, we can quickly set up "Replace Rules for switching API & Javascript Hosts" and load selective (or all) APIs from the local environment directly on higher environments. This saved us a lot of hassle, time & effort in working across environments. It's a go-to tool every day for Devs & QAs now.
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Michael Levinson
CPO & Co-Founder
Requestly not just made it easier for us to develop, test & debug our code on our customer sites but It also helps us do engaging product demos to our prospective clients.
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Piers Carrigan
QA Lead
Requestly is a game-changer for us. It started with one person and now the entire team uses Requestly to test our Staging code on production customers & non-customer sites. We more confidently ship product updates now.
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Robert Wharton
Senior Product Manager at Metrical
Requestly has been a lifesaver for testing our product on our customers websites. Everyone's stage sites are a hot mess of half finished dev projects, but Requestly allows us to mock up stage sites in seconds that better reflect the live sites!
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Nitish Mittal
Director of Engineering at Wingify
Requestly is one-stop solution for all our needs at Wingify. Collaboration feature works like a Charm. Our devs & QAs collaborate on Requestly Rules while debugging & testing campaigns.
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Kushagra Gour
Frontend Lead at PushOwl
Requestly’s Script Modification Rule feels like magic. Me & my team actively use Requestly to test our local changes on the customers websites and ensure we deploy no-breaking changes in production.
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Param Aggarwal
Engineering Manager at Cult.fit
It allows me to convert my Chrome browser into a supercharged development tool by creating advanced rules to modify the requests that the website is making. Very useful to quickly tweak API parameters and image resolutions without any code change!
Mukul Gupta
Senior Software Engineer at Adobe
I'd rate it as one of the best extensions around to boost developer productivity. Even if you're not a developer but need to navigate through loads of seemingly similar web pages, it is highly recommended with a very small learning curve.
Varun Jain
Co-Founder at SendX
Requestly just works :) We are one of the paid users. We have been using Requestly to debug SendX Javascript API on our client's websites and Requestly has saved ton of debugging time for us.
Robert Wharton
Senior Product Manager at Metrical
Requestly has been a lifesaver for testing our product on our customers websites. Everyone's stage sites are a hot mess of half finished dev projects, but Requestly allows us to mock up stage sites in seconds that better reflect the live sites!
Rafael Gibelli
Compra Rapido YC W'22
Requestly is a fantastic tool. It has made our team's life so much easier and more productive. Totally Recommend!
Kos Breton
Director (Management) at Coinbase
Thank you for making this great addon. I just checked out Requestly and indeed it is very easy to set up. It helps me customize my browsing experience entirely. Keep up the great work!