De MonsterDebugger is an open source debugger for Adobe Flash, Flex and AIR. De MonsterDebugger is made in Flex and AIR by design studio De Monsters.

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Buzz. While De MonsterDebugger hasn't been around for that long, it has already created a lot more buzz than we thought it would in such a short period of time. Without all these articles and screencasts there would be a lot less people who could benefit from De MonsterDebugger. We greatly appreciate everyone for helping us spread the word on De MonsterDebugger. Please let us know if you find a nice article somewhere by emailing us at

Debugging with MonsterDebugger - Learn how to debug your Flash movies at runtime with this great debugging tool.
May 8th 2009
I have just uploaded a new tutorial that shows you how to debug your Flash movies at runtime using the MonsterDebugger AIR application. This well designed application allows you to view and modify all of your objects and methods at runtime and contains a host of advanced features. It also features a very clean CS4-like interface which I love. This tool works equally well for Flash, Flex, and AIR applications.

AdobeAirApps A Fresh Breath of AIR
June 12th 2009
AdobeAirApps has a growing collection of Adobe AIR applications.

Alcon Vs De MonsterDebugger
June 12th 2009
I Was trying out these 2 Flash / Flex / Air debugger for a few days and i strongly recommend these 2 applications to any actionscript developers...

The Flex Show Episode 73: Interview with Ferdi and Paul from De Monsters
May 13th 2009
This week we speak to Ferdi Koomen, and Paul Reijnierse from De Monsters about one of their products, De Mosnter Debugger.

De MonsterDebugger (Chinese)
May 10th 2009

De MonsterDebugger (Japanese)
May 13th 2009
Another how-to-guide showing live editing, method testing and detailed traces.

A great new debugger tool for Flash, Flex and Air applications
May 12th 2009
I came across a really nice debugger tool to debug flash, flex and air applications at run-time. It is De MonsterDebugger This is by far the best debugging applications I have seen.

De MonsterDebugger (Asian)
April 4th 2009
A brief how-to-guide explaining the tree structure, detailed traces, live editing and method testing.

Smashing Magazine: Adobe AIR Developer's Toolbox: Resources And Tutorials
April 7th 2009
De MonsterDebugger is an open-source debugger for Adobe Flash, Flex and AIR. De MonsterDebugger itself was built with Flex and AIR.

Smashing Magazine on Adobe AIR
April 7th 2009
Smashing Magazine has a pretty comprehensive collection of AIR resources and tutorials up on their site today. They feature all of the Adobe hosted stuff (official resources, support, free samples, etc.) as well as highlighting some of the better community resources including, Aptana Studio, and the De MonsterDeBugger.

Great looking AIR based debugger for Flash, Flex and AI.
April 3rd 2009
Today, i found another great looking AIR based debugger - De Monster Debugger. It is created by Design Studio DeMonster.

De MonsterDebugger at Swiss Flash User Group
March 30th 2009
During the latest Swiss Flash User Group Meeting Sandro Ducceschi (Liip AG) spoke about debugging Flash using De MonsterDebugger.

You can find the presentation that Sandro gave right here:

16 Fresh Adobe AIR Applications For Designers & Developers
March 25th 2009
An open source debugger for Adobe Flash, Flex & AIR. It can trace strings, numbers, objects, arrays, xml and even custom classes, edit properties in runtime, explore your live application & much more.

De MonsterDebugger
February 17th 2009
De MonsterDebugger is an incredible new AIR app from De Monsters which allows you to debug AS3 Actionscript/Flex projects on the fly.

De MonsterDebugger: Nieuw Open Source Debugger (Dutch)
February 14th 2009
De MonsterDebugger is een open source debugger voor Adobe Flash, Flex and AIR. Aangezien XRay lijkt dood te zijn en SOS niet meer is dan een tracer, lijkt dit ons een uitstekend nieuwe initiatief!

Another great AS3 Debugging tool
February 14th 2009
Here's another great Debugging tool for flash AS3 - It allows you to drill down to the properties of objects at runtime and even change them on the fly! It's a little more complex to use, but very powerful.

De MonsterDebugger: Neuer Stern am Debugger-Himmel (German)
February 9th 2009
Vor kurzem habe ich gesehen, dass es einen neuen Debugger mit dem Namen De MonsterDebugger gibt. "Naja, gibt es ja schon genügend", dachte ich zuerst. Ein näherer Blick belehrte mich eines Besseren, die Möglichkeiten des Debuggers sind "monstermäßig".

De Monster Debugger - Video Intro
February 6th 2009
The video simply shows how to download, install and use with a simple Actionscript Project in Flex Builder 3.

Debug Flash/Flex & Air with De MonsterDebugger
February 5th 2009
I highly recommend this debugger. It is an AIR application that has many useful features and will make your life much easier.

Debug Flash/Flex & Air with De MonsterDebugger
February 5th 2009
I highly recommend this debugger. It is an AIR application that has many useful features and will make your life much easier.

De MonsterDebugger rocks
February 5th 2009
This ist just too cool For quite a while I was using Alcon as my default debugger for any kind of flash / flex applications, today I just found this awesome Debugger which caught my eyes, not only because the cool logo but mainly because of the possibilities.

De MonsterDebugger v2.0 für Flash, Flex, AIR (German)
February 5th 2009
Wer eine Alternative zum Build-In Debugger von Adobe sucht, sollte sich mal "De MonsterDebugger" anschauen.

Screencast: De MonsterDebugger, o super tracer para Flex/AIR e Flash (Brazilian)
February 5th 2009
Pois foi deste último que veio a dica do De MonsterDebugger, produto open source desenvolvido pelos caras do De Monsters, studio holandês de desenvolvimento.

There is a screencast that goes with this article, it has a Portuguese voice-over and can be found here:

De MonsterDebugger (French)
February 5th 2009
De MonsterDebuger permet de débuggeur du Flash, du Air et du Flex. Créé par la société De Monsters, il est open source et a des fonctionnalités plutot intéressantes comme le "Live Editing" ou "Tree Structure".


Official MonsterDebugger T-shirt

Do you 'kill bugs like a Monster'? Show it to the rest of the world by wearing an official MonsterDebugger T-shirt. You can order them right here. (Europe only at the moment)

Since we do this for the community, we don't charge any commission.

Download MonsterDebugger version 2.5.1 (examples included)

If you share our ambition for clean coding and easier debugging please help us by spreading the word.