Welcome to the website of JKP Application Development Services

What I do

Services

I offer services pertaining to any aspect of Excel and VBA. My Services page shows you examples of services I provide. You will also find a list of recent projects there.

Products

I develop bespoke Excel tools for customers and also Excel add-ins for the general public, like my spreadsheet auditing tool RefTreeAnalyser. Check out products I have developed.

Training

Go to LinkedInLearning for the only Excel course aimed at engineers: Excel for Engineering Professionals

Check out my Excel training page for other training options.

Newsletter

Subscribe to our news letter or check out the archive. There is no set frequency, I just post something when I have time. In any case, it is all about Excel.

Free Excel downloads

I develop custom-made applications using Microsoft Office Excel® and VBA and Access and VBA to their full extent. Have a look at various (free) downloads, some of which have become the de facto standard for Excel developers around the world.

Who is Jan Karel?

Would you like to learn more About me? On this page you can get to know me a little better and also find a short list of presentations I've given over the past years.

MVP

I've been granted the Microsoft MVP award each year since 2002!

What's new on this site

English and/or Dutch content

Updated: Name Manager JavaScript edition

Today my Name Manager (JS edition) has been updated. Get your update by clicking in its task pane and pressing control+F5. Changes include: Added a Lambda Name Type filter

Fri, 27 Sep 2024 13:30:00 GMT

I've added a chapter on VBA issues to my Excel troubleshooting page.

Thu, 26 Sep 2024 15:45:00 GMT

I've updated Autosafe with a new method for checking for updates.

Thu, 26 Sep 2024 09:30:00 GMT

RefTreeAnalyser has just been updated to version 3.1, build 213. Improved error tracing. No longer removes hotkey preferences when add-in is uninstalled. Handle new 'trim empty cells' reference. Improved display of values in precedents tree. Improved design of precedents/dependents form for better readability. Removed $ signs from cell references in some labels for better readability. Fixed issue with @ references.

Wed, 18 Sep 2024 17:00:00 GMT

RefTreeAnalyser has just been updated to version 3.1, build 212. Fixed issue where visible area changes when tracing dependents. Fixed range selection when reference is outside of the viewable range. Improved filtering of found objects.

Thu, 22 Aug 2024 16:45:00 GMT

As of today, all pages formerly hosted by Ron de Bruin can be found on my site. It will take quite some time to update these pages and fix broken links.

Thu, 15 Aug 2024 16:10:00 GMT

Flexfind (VBA edition) was updated so addresses of cells are shown without $ characters

Wed, 31 Jul 2024 16:10:00 GMT

Today I've updated my Flexfind (JS edition). I've added an option to either search in Values or in Formulas and Contiguous ranges are now displayed as one block (A1:B2) instead of as individual cells. To get the update, load the add-in in the usual way, click in it's pane and press control+F5

Tue, 04 Jun 2024 14:40:00 GMT

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