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. I've Added a new Type filter: Tables. This allows you to list all tables in your workbook.

Tue, 15 Oct 2024 16:30:00 GMT

If you've ever used the Analysis toolpak add-in you know it produces static output. This new download duplicates the output of the ATP, using formulas. Includes the full ANOVA output and all.

Mon, 14 Oct 2024 12:45:00 GMT

Name Manager has just been updated to build 709. Added a new system name to the Excel system names filter.

Tue, 08 Oct 2024 10:30:00 GMT

RefTreeAnalyser has just been updated to version 3.1, build 214. If a formula contains a named range, it now displays the formula of that named range and its precedents.

Mon, 07 Oct 2024 15:15:00 GMT

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

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