Excel Document working very slow

a lot of data? a lot of formulas that cover entire columns rather than specific ranges - I had one like that that when I changed it from whole columns to specific ranges it dropped it in size from over 35,000kb to just over 3,000kb and that was the only change I made.

How is it slow? Slow top open/close/save? Slow calculations? Slow performing any action (copy, paste, filter, sort, etc)? Specific macro or formula is slow?

Whats the file size of the file? Roughly how many sheets, rows and columns per sheet?

Can you post a sample file with the problem?

Do you get any error messages?

The document is working slow in general (when opening, performing actions, editing etc)... The file size is 1,67MB, with 6 sheets with 1000+ lines each, 15+ columns. Actually no message error while editing or opening or in any momment.

I can't post the sample cause there's confidential information in the doc

Ok. The file size seems to be reasonable considering the content then, so unlikely its a substantial amount of excess content.

Is the file stored on a network drive, in the cloud or on a local drive? If its on a network drive, make a copy locally and open it, does it still seem slow? If not then its a network bottle neck...not much you can do in that case other than let IT dept know (if this is at work and they have an IT dept). If it still has the issue, do you have another file of a similar file size you can try. If that works fine then something about the file is making it slow.

Does the problem happen if you open Excel in safe mode and open the file from within Excel while in safe mode? If not its likely an add-in causing problems.

Do other people use the file too, do they have the problem?

In the status bar at the bottom right, do you get "calculating on x cpu's..." or a similar message when things are slow?

Is it possible to remove the confidential information to post a sample? Without being able to see the issue first hand we are basically guessing.

Do you have a lot of array formulas, or lookup type formulas? Any volatile ones like OFFSET, INDIRECT, TODAY?

Not really, there's a lot of SUMIF and SUM, sometimes more than 6 SUMIF in the same cell