Slow Workbook calculation

Hi Aspose team!

When we recalculate a workbook using workbook.CalculateFormula(true, false, null), (CreateCalcChain = false) it takes about 50 minutes to complete with average CPU usage about 30%. The same operation in MS Excel takes at least twice less time with almost 100% CPU usage (screens are attached). It seems not to be good. Is it possibe to speed recalculation up? What can be done for it?

Best regards,


Thanks for your posting and using Aspose.Cells.

Please download and try the latest version: Aspose.Cells
for .NET v8.6.0.2
and see if it makes any difference and resolves your issue.

If your issue still occurs the please provide us your sample code or sample console application project along with your source excel files for our investigation. We will look into it and help you asap.


Thanks for your attention!

The latest version doesn’t help. Here’s our sample application with excel file:


Thanks for your posting and using Aspose.Cells.

We have tested this issue with the following sample code using the latest version but the process seems to be taking lot of time. Although the file size itself is large so it seems to be a usual thing.

We have therefore logged this issue in our database for investigation. We will look into it and improve if if possible. Once, there is some news for you regarding this issue we will update you asap.

This issue has been logged as

  • CELLSNET-43945 - Slow Workbook calculation

string filePath = @“D:\Downloads\templates\case1.xlsx”;

Workbook workbook = new Workbook(filePath);

Stopwatch sw = new Stopwatch();




Debug.WriteLine("--------------" + sw.ElapsedMilliseconds);

+100500 to the originator!!

We also had experienced low CPU usage when calculating large data sheets in Aspose.Cells. This critical issue (and a few less critical) stopped us to migrate from Interop Excel Automation to Aspose.Cells. Also we have discovered that CalcChain xml-part is never written to the output file by the Aspose.Cells. Perhaps this is related to the problem…

But… Aspose is the best excel-file-handling library! It works where other libraries throws an exception when trying to load very complex xlsx-file well-formed by MS Excel app (it’s a fact. not an advertising).


Thanks for your posting and using Aspose.Cells.

We have logged your comment in our database against this issue for product team consideration. We will look into it and implement/fix it if possible. Once we will have some update for you, we will let you know asap.


Thanks for using Aspose.Cells.

The reason of lower CPU usage is because Aspose.Cells does not support multi-threads calculation. As you might have found, ms excel can use the total 4 cpus when calculating formulas but Cells can only use one of them. We may consider to improve our calculating engine with support of multi-threads in future for newer versions, but it is a complicated task to rebuild cells model to support multi-threads calculation and we are afraid we cannot support it soon.


Thanks a lot for your attention. I hope waiting won’t be too long!