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File crashes Excel!!

Save my workbook!
The best tool for salvaging problematic workbooks.


Excel VBA Masterclass (English)
Excel VBA for Financials (Dutch)

Third party tools

Speed up your file

The best tool to optimise your Excel model!

What has changed?

PerfectXL Compare, for Spreadsheet Comparison
This Excel compare tool is fast, reliable, and easy to use. Compare two Excel files now and see for yourself!
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Here are some of the products developed by JKP Application Development Services.

Find a list of recent projects here.


The ultimate Excel formula auditing tool!

Ever had to work out the logic of other people's Excel files? Ever had to untie the spaghetti-knots of a large Excel workbook's formulas? Then you know what a nightmare this can be!

Now there is the RefTreeAnalyser!

Excel file remediation tool

Many companies have been using spreadsheets for decades. Sometimes, intricate spreadsheet models get into trouble. The file opens with error messages, or error messages start to surface as soon as any formatting is changed. This tool is designed to try to salvage as much as possible from those files. Read more about the file remediation tool.

Free Excel add-ins, Access tools and example workbooks

See the download page for all our free utilities and Excel add-ins.