
November 10, 2022
Top 21 Google Tag Manager Extensions and Tools for Fast and Efficient Work
Updated: November 10th, 2022.
A lot of new things have happened in the industry since the first time when I published this blog post (back in early 2017). Almost three years have passed and a lot of new tools were developed (or discovered). The time has come for the 5th version of this list.
If you’re using Google Tag Manager as often as I do, you’re probably looking for new ways to improve your performance, catch bugs faster and deliver the final result without much hassle. If my guess was right, you’ll enjoy these 21 Google Tag Manager extensions and tools (and not all of them are just for Google Chrome). And the best part – they’re all free! So do not hesitate and give them a shot.

All Google Tag Manager Extensions are displayed in no particular order.
- Tag Assistant (Legacy) + Tag Assistant Companion
- Data Slayer
- WASP
- Da Vinci Tools
- GTM Sonar
- dataLayer Inspector+
- GTM Variable Builder
- Data Layer Checker
- Copy CSS Selector
- GTM Tools
- customTask Builder
- GTM Debug
- SandoGTM
- GTM Spy
- GA Debugger
- EditThisCookie
- Redirect Path
- Facebook Pixel Helper
- Twitter Pixel Helper
- UET Tag Helper
- Tag Assistant Companion
#1. Tag Assistant (legacy) + Tag Assistant Companion
The Tag Assistant Chrome extension is a very useful tool for testing and debugging your implementation. Not only does it help with troubleshooting Google Tag Manager, but also Google Ads, Analytics, DoubleClick, and other tools can be easily verified.
One of the most powerful features within the extension is recordings. This allows you to “record” a browsing session and produce a report on all of the hits being sent through and even how they will potentially show up within Google Analytics. By the way, you can find my guide on this extension here.
However, as you have already noticed, the name of the extension contains the word “Legacy”. Eventually, this extension will be deprecated. So if that happens, then you can use a lighter version of the extension, and it is called Tag Assistant Companion. Even though it does not have Legacy’s debugging features, it will still enhance your GTM’s preview and debug mode.
#2. Data Slayer
Another entry in this list of Google Tag Manager Extensions, Dataslayer, adds a panel to Chrome Developer Tools that monitor tag management data layers and displays changes in an easy-to-read, user-friendly format.
Not only does it support Google Tag Manager, but it also plays well with Tealium.
#3. Web Analytics Solution Profiler – WASP
Update: It looks like this plugin is no longer available, as it returns a 404 error in the Chrome Store. However, I’ll still keep this here for a while (because maybe that’s a temporary issue).
This extension is for advanced users. WASP gives you a visual representation of the tags firing on your site and the correlation between them.
Clicking any of the tags provides deep technical insight into what’s happening behind the curtain. WASP’s functionality allows you to peer into the Google Tag Manager data layer which eases the troubleshooting of Google Tag Manager and Universal Analytics implementations.
WASP also supports Omniture, SiteCatalyst, DoubleClick, and any other platforms you may be implementing.

#4. Da Vinci Tools
Da Vinci Tools brings handy enhancements, bug fixes, and hacks directly into the Google Analytics and Google Tag Manager interfaces. To name a few:
- Focus on the same report when switching view in Google Analytics
- Set default page in GTM interface (instead of Overview)
- Ability to turn all GTM built-in vars on/off at once
- Ability to copy values from GTM Preview and Debug Mode’s Data Layer Tab and many, many other enhancements.
And I’m just scratching the surface here! Many more enhancements are waiting for you.
#5. GTM Sonar
Created by Simo Ahava, this extension lets you debug clicks and form submissions easier. When enabled, it prevents links from redirecting you to another page and form submissions from refreshing/redirecting you to another page.
Why prevent the default action of click or form submission? For debugging reasons, it’s better if you stay on the same page. Halting the default action prevents links from working, thus you can easily check what happens on a website and what data can be used for tracking purposes.
#6. dataLayer Inspector+
This is one of my new favorites. What I like about it, is that the extension (by Adswerve) can inject your GTM container on a site, logs what data was pushed to dataLayer, runs diagnostics for most common issues, and offers a bunch of other features. I’m also giving a closer look at this extension in my Intermediate GTM course.
Get dataLayer Inspector+ for Chrome
#7. GTM Variable Builder
This useful plugin enables you to easily create Custom JavaScript variables that retrieve values of particular website elements. If you’re not familiar with the DOM variable, feel free to use this extension.
How does it work? Open the JavaScript console in Chrome, highlight any element on a website, and click the extension icon. What you’ll get is the JavaScript function that should be used in a GTM Custom JavaScript variable.
#8. Data Layer Checker
Another extension to help you easier debug what’s happening in the Data Layer. But unlike Data Slayer or Data Layer Inspector, this plugin enables you to check the Data Layer without having to use the browser console.
Which one is better, you ask? Well, it’s up to you. Try all three and see which one fits your needs the best. My personal favorite is Data Layer Inspector because it also offers a bunch of other features, like injecting GTM containers.
But if you don’t need the Swiss army knife and want to debug the Data Layer, maybe Data Layer Checker could be your choice.
We’re halfway through. 10 Google Tag Manager Extensions down, 10 to go! There are some gems waiting for you, so don’t go away and continue reading.
#9. Copy CSS Selector
If you’re regularly working with Matches CSS Selector operator in Google Tag Manager, then this extension is for you. Why is it useful? If you struggle with CSS Selectors or just want to save time, Copy CSS Selector will do the work for you. Just right-click the website element you wish to track, hit Copy CSS Selector, and paste the selector in your Google Tag Manager Trigger.
If you don’t know what CSS Selectors are, read this Simo Ahava’s guide. They are especially useful (but not limited to) when you want to track clicks of a particular website element that has no ID and shares the same CSS Class as several other elements.
Learning some basics of CSS Selectors opened new possibilities for me, so you should definitely dig in too.
#10. GTM Tools
Another very useful tool created by Simo Ahava. This time, it’s not a Google Tag Manager Chrome extension but a hosted web tool that helps me audit and manage/clone GTM container. It has three main features:
- Container visualization (with it, you can find which container elements are heavily used or are not used at all).
- Inspect container
- Clone container. I’ve used this feature to export a part of a GTM container (because, by default, GTM exports the entire container). However, there’s a new player in the town, a Google Tag Manager Extension (for Chrome), that can help you do that even faster. Continue reading, and I’ll show you what I mean.
#11. customTask Builder
Simo Ahava developed this too. If you’re not familiar with a Custom Task yet, read Simo’s guide first. In a nutshell, customTask is a method of the Universal Analytics library, which lets you run JavaScript code when the hit request to Google Analytics is being built.
There is a whole bunch of possible ways how customTask can be applied. To name a few: remove Personally Identifiable Information from GA hits, automatically reduce the GA payload size, and many more. Since this feature is an advanced one, Simo Ahava prepared a customTask builder tool that will simplify the process.
Note: this is useful for Universal Analytics (GA3), not GA4 (as it does not support customTask).
#12. GTM Debug
An amazing Chrome extension developed by David Vallejo that eases the process of Google Tag Manager debugging. Among many useful features, here are the most noteworthy (in my opinion):
-
- Copy Data Layer pushes in a formatted way
- Ability to view Data Layer pushes of previous pages
- Filtering by GA Hit Type or GA account ID
-
- Simplified Enhanced Ecommerce debugging (I’ve used this GTM extension in the Enhanced Ecommerce module of my Intermediate GTM Course. A real time-saver).
These and other useful features are waiting for you in that GTM extension, so definitely try it out.
#13. SandoGTM
Recently, I stumbled upon this Google Tag Manager Chrome extension and probably haven’t uncovered its full potential yet. However, it looks really useful and offers some handy tweaks that Google Tag Manager’s UI lacks.
Get this Google Tag Manager extension
#14. GTM Spy
This free tool (no signup required) lets you check what’s inside of the GTM container of any website. This can help you with spying on the competitor or recreate the content of the container that you lost access to. I’ve heard multiple situations where rogue agencies lock the client away from the container (even though that container is the client’s property).
In such cases, you could just use GTM spy and export the container that is used on your own website. Then create a new GTM container and import the file you exported via GTM Spy. Finally, ask your developers to change the container ID in your website’s source code. That way, you’ll solve this nasty issue with the agency.
Keep in mind that GTM spy has some UI/UX issues, but as long as it is working (and free), we can live with that.
The next extensions are useful even if you’re not using Google Tag Manager. But since I am implementing (almost) everything with GTM, these tools always come in handy.
#15. Google Analytics Debugger
This extension lets you see what data is being passed to Google Analytics. For me, this was extremely useful while debugging Ecommerce implementation (until the GTM Debug extension was created by David Vallejo).
It prints useful information to the Javascript console of your Chrome browser. These messages include error messages and warnings which can tell you when your analytics tracking code is set up incorrectly. In addition, it provides a detailed breakdown of each tracking beacon sent to Google Analytics.
Get Google Analytics Debugger for Chrome
#16. Edit this Cookie
With it, you can view cookies set by Google Analytics, delete, modify, and even add additional cookies. This is a great tool for verifying GA trackers and any other custom cookies that may be in use.
Although you can also achieve the same result with the built-in tools of your web browser, Edit this Cookie makes the process much easier and user-friendly.
For me, this is a must-have tool when I set and read cookies with Google Tag Manager. Even though you can achieve pretty much the same result by using the browser’s built-in functionality, this extension makes the work easier.
Get Edit This Cookie for Chrome
#17. Redirect Path
This extension allows you to easily see all the redirects that happened between two pages. One of the most popular use cases for me: Debugging of Cross-domain tracking. One of the main requirements for GA cross-domain tracking to work is to have the destination URL decorated with the linker parameter (_ga=……).
But what if you’re configuring the cross-domain setup but the target URL never gets decorated? Two possible reasons are:
- The link was never decorated on the initial page
- Between two pages, there were multiple redirects and during one of them, the linker parameter (_ga=…) was lost
Redirect Path extension can help you identify such an issue. Just install it, navigate from page A to page B (while debugging your cross-domain setup) and then click the extension’s icon in the top right corner of your Chrome.
In the example above, there was one redirect. The kwikipedia.org URL contained the linker parameter but after the redirect (type 302) the parameter was lost. If that’s your case, contact the developer of the site and discuss how can they fix this (because it’s impossible to fix this with GTM).
#18. Facebook Pixel Helper
The Facebook Pixel Helper is a troubleshooting tool that helps you validate your Facebook Conversion Pixel and Custom Audience Pixels. Using the tool you can verify whether the pixel is working properly, what events were fired, and spot errors in no time.
A small number will appear on the Facebook Pixel Helper icon to indicate the number of pixel events. When clicked, a panel will expand to show a detailed overview of the page’s pixels, including warnings, errors, and successes.
Either you’re installing Facebook pixel or tracking FB conversions with Google Tag Manager, Facebook Pixel helper is a no-brainer and reliable debugging companion.
Get Facebook Pixel Helper for Chrome
#19. Twitter Pixel Helper
Similarly to Facebook Pixel Helper, Twitter Pixel Helper does the same job, but for Twitter Universal Website tag.
You can check whether the Twitter Tracking code (Pixel) was implemented successfully. Troubleshooting of Twitter events (conversions) is also available.
Get Twitter Pixel Helper for Chrome
#20. UET Tag Helper
The third Pixel Helper in the gang. This one helps with debugging and validating Bing’s UET (Universal Event Tracking) tags. Here a quick intro video about this extension.
#21. Tag Assistant Companion
When a new version of the GTM preview mode was introduced, and Google Tag Assistant was declared as Legacy, Google introduced Tag Assistant companion. This extension is designed to improve the user experience of the new preview mode. If you already have Google Tag Assistant (Chrome extension) installed, there is no need to have the companion extension too. They improve the GTM preview mode in the same way.
However, if you haven’t done that yet, then you should install Tag Assistant companion. You can learn more about its benefits here.
Google Tag Manager Extensions: Final Words
All great things must come to an end, even this list. I hope you found the collection of Google Tag Manager Extensions and tools useful. Spotted something new? Give it a try! Maybe you’ll love it. I often use:
- Tag Assistant (or Tag Assistant Companion)
- Data Layer Inspector
- Redirect Path
- GTM/GA Debug
- Da Vinci is working in the background
- GA Debugger
Although, I have to admit that the more I experienced become, the more I use just native developer tools of a browser.
Did I miss some Google Tag Manager Extensions you can’t imagine your work without? Let me know in the comments below!

7 COMMENTS
Hi Julius,
May I know if WASP is still available? If not, do you have recommendation for replacement? thanks a lot!
Looks like it was removed from chrome store yesterday. Don't know what is the future of it.
I am not aware of any alternatives.
Hello Julius,
I am trying to audit a website for client to suggest improvement/recommendation. I am using "GTM/GA Debug" and "GA Debugger". I can't see the event names while firing. Is it possible to see the "events" , "triggers" by using some extension ?
Also, what would be the preferred tools or things to check/keep in mind you would suggest for this type of auditing.
Thanks in advance,
I'd like to share also https://gtmutility.com which is a web based tool ;) You can visualize the GTM container setup in a form of the flowchart or load all parameters of the core Google tags in the tabular view.