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.

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. New filter: Volatile names (names containing volatile functions like OFFSET and RAND). New filter: Names referring to entire rows or columns. New option: You can now edit the name and range of a table.

Wed, 20 Nov 2024 10:00:00 GMT

Update: RefTreeAnalyser

RefTreeAnalyser has just been updated to build 218. Removed short-cut keys for Name Manager and FlexFind (these are now controlled by these add-ins). Fixed bug in Object references. Improved Tile function. Fixed bug in finding references when the active cell is a named range.

Fri, 15 Nov 2024 16:30:00 GMT

Update: RefTreeAnalyser

RefTreeAnalyser has just been updated to version 4.0, build 217. I've Integrated two popular addins (which also auto-update): 1. FlexFind, 2. Name Manager. Added sheet and table drop-downs to the ribbon for quick navigation. Improved the UI, like tooltips. Detects when a policy disables ribbon customization (which causes the RefTreeAnalyser tab not to appear).

Tue, 12 Nov 2024 16:00:00 GMT

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: Duplicate. filters the names list to only duplicate workbook-level and worksheet level names.

Mon, 11 Nov 2024 14:00:00 GMT

Update: RefTreeAnalyser

RefTreeAnalyser has just been updated to version 3.1, build 216. Several bug fixes regarding ribbon handling and menu creation have been implemented.

Fri, 18 Oct 2024 15:00:00 GMT

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

New download: Least squares linear regression

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

Update: Name Manager

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

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