How To Make Open Office Excel Stop Calculating

Calculate how to stop unnecessary calculations and improve spreadsheet performance

Comprehensive Guide: How to Make OpenOffice Excel Stop Calculating

OpenOffice Calc (the spreadsheet component of Apache OpenOffice) automatically recalculates formulas whenever you make changes to your spreadsheet. While this feature ensures your data is always up-to-date, it can significantly slow down performance—especially with large or complex spreadsheets. This guide explains multiple methods to control or stop automatic calculations in OpenOffice Calc.

Why Stop Automatic Calculations?

There are several scenarios where you might want to disable automatic calculations:

• Performance issues with large spreadsheets containing thousands of formulas
• Working with volatile functions that recalculate constantly (e.g., NOW(), RAND(), TODAY())
• When you need to enter large amounts of data without waiting for recalculations
• During development of complex models where intermediate results aren’t needed
• To prevent circular reference errors from causing infinite loops

Method 1: Switch to Manual Calculation Mode

The most straightforward way to stop automatic calculations is to switch to manual calculation mode:

1. Open your OpenOffice Calc spreadsheet
2. Click on Tools in the menu bar
3. Select Cell Contents (or Calculate in some versions)
4. Choose Manual from the calculation options

Note: In manual mode, you’ll need to press F9 to recalculate when needed. You can also use:

• Shift+F9 to calculate the current sheet only
• Ctrl+Shift+F9 to calculate all sheets in all open documents

Calculation Mode	When It Recalculates	Best For	Performance Impact
Automatic	After every change	Small spreadsheets, real-time data	High (can be slow with complex sheets)
Manual	Only when you press F9	Large spreadsheets, data entry	Low (best for performance)
Automatic except for data tables	After changes, but skips data tables	Sheets with data tables	Medium

Method 2: Optimize Volatile Functions

Volatile functions recalculate every time OpenOffice Calc recalculates, regardless of whether their dependencies have changed. Common volatile functions include:

• NOW() – Returns current date and time
• TODAY() – Returns current date
• RAND() – Returns random number
• CELL() with certain parameters
• INDIRECT() – When referencing volatile ranges

Solutions for volatile functions:

1. Replace with static values when possible (e.g., paste as values after calculation)
2. Use non-volatile alternatives:
   • Instead of NOW(), use a timestamp macro or manual entry
   • Instead of RAND(), generate random numbers once and copy as values
3. Isolate volatile functions in a separate sheet that calculates manually
4. Use named ranges instead of INDIRECT() where possible

Method 3: Reduce Formula Complexity

Complex formulas with multiple nested functions or array operations can significantly slow down calculations. Consider these optimization techniques:

Optimization Technique	Before	After	Performance Improvement
Break down complex formulas	=IF(AND(A1>10,B1<5),SUM(C1:C100)/AVERAGE(D1:D100),0)	Use helper cells for intermediate calculations	30-50%
Replace array formulas	{=SUM(IF(A1:A100>10,B1:B100))} (array formula)	Use SUMPRODUCT or helper columns	40-70%
Use efficient functions	=VLOOKUP() with approximate match	=INDEX(MATCH()) combination	20-40%
Limit used range	Full column references like A:A	Specific ranges like A1:A1000	10-30%

Method 4: Manage Data Tables

Data tables in OpenOffice Calc can cause performance issues because they recalculate whenever their input cells change. To optimize:

1. Convert to values when the analysis is complete:
   • Select the data table range
   • Copy (Ctrl+C)
   • Paste Special → Values (Ctrl+Shift+V)
2. Use manual calculation for sheets containing data tables
3. Limit the size of your data tables to only what you need
4. Avoid nested data tables which can cause exponential calculation times

Method 5: Disable Add-ins and Extensions

Some OpenOffice extensions can trigger recalculations or run background processes. To check:

1. Go to Tools → Extension Manager
2. Disable any extensions you're not actively using
3. Restart OpenOffice Calc
4. Test if performance improves

Common performance-heavy extensions include:

• Financial analysis tools
• Statistical add-ins
• Database connectivity extensions
• Custom macro collections

Method 6: Adjust OpenOffice Calc Settings

Several hidden settings can affect calculation performance:

1. Increase the number of threads (for multi-core processors):
   • Go to Tools → Options → OpenOffice Calc → Calculate
   • Adjust "Threads for calculation" to match your CPU cores
2. Limit iteration calculations:
   • In the same options menu, reduce "Maximum iteration count"
   • Increase "Maximum change" to stop iterations sooner
3. Disable "Calculate formulas automatically" in the Load/Save options
4. Increase memory allocation:
   • Go to Tools → Options → Memory
   • Increase "Number of objects" and "Memory per object"
   • Enable "Use for OpenOffice"

Method 7: Use Alternative Approaches

For extremely large or complex spreadsheets, consider these alternative approaches:

• Split into multiple files and link them with DDE or external references
• Use a database (Base) for data storage and Calc for analysis only
• Export to CSV and process with specialized tools
• Use macros to control when calculations occur
• Consider alternative software like:
  • LibreOffice Calc (often better performance)
  • Gnumeric (lightweight alternative)
  • Python with pandas for data analysis

Troubleshooting Common Issues

If you're still experiencing problems after trying these methods:

Problem	Possible Cause	Solution
Calc freezes during calculation	Infinite loop from circular references	Go to Tools → Detective → Circular References Switch to manual calculation to break the loop Fix or remove circular references
Calculations take too long	Too many volatile functions or array formulas	Identify volatile functions with Tools → Auditor Replace with static values where possible Break down complex array formulas
Wrong results after manual calculation	Dependencies not recalculating properly	Press Ctrl+Shift+F9 to force full recalculation Check for #VALUE! errors that might block calculations Verify all dependencies are included in calculation
Performance degrades over time	Memory leaks or fragmentated file	Save and restart OpenOffice Calc Export to new file (Save As) Clear undo history (Edit → Undo → Clear)

Best Practices for Long-Term Performance

To maintain optimal performance in OpenOffice Calc:

1. Regularly clean up your spreadsheets:
   • Remove unused cells, sheets, and named ranges
   • Delete hidden rows/columns that aren't needed
   • Clear formatting from unused areas
2. Use styles consistently instead of manual formatting
3. Limit conditional formatting to essential ranges
4. Avoid merging cells which can cause calculation issues
5. Document your formulas to make maintenance easier
6. Save versions before making major changes
7. Test performance with Tools → Auditor regularly

Advanced Techniques for Power Users

For users comfortable with more technical solutions:

1. Use OpenOffice Basic macros to control calculations:

   Sub ToggleCalculationMode
       Dim oCalc as Object
       oCalc = ThisComponent.CurrentController
       If oCalc.CalculationMode = com.sun.star.sheet.CalculationMode.AUTOMATIC Then
           oCalc.CalculationMode = com.sun.star.sheet.CalculationMode.MANUAL
       Else
           oCalc.CalculationMode = com.sun.star.sheet.CalculationMode.AUTOMATIC
       End If
   End Sub

2. Modify configuration files:
   • Edit registrymodifications.xcu to set default calculation modes
   • Adjust memory settings in sofficerc
3. Use command line options:

   soffice --calc "--accept=socket,host=localhost,port=2002;urp;StarOffice.ComponentContext" &
   soffice --connect "socket,host=localhost,port=2002" "macro:///Standard.Module1.ToggleCalculationMode"

4. Create custom calculation chains using the API to control calculation order

Authoritative Resources

For more technical information about OpenOffice Calc performance optimization:

• Official OpenOffice Documentation - Comprehensive guides on all Calc features
• The Document Foundation Wiki - Technical details about Calc's calculation engine
• NIST Spreadsheet Standards - Best practices for spreadsheet development from the National Institute of Standards and Technology

Frequently Asked Questions

Q: Will switching to manual calculation affect my formulas?

A: No, switching to manual calculation only affects when calculations occur. All your formulas remain intact and will produce the same results when you manually recalculate (F9).

Q: How can I tell which formulas are slowing down my spreadsheet?

A: Use these techniques to identify problematic formulas:

1. Switch to manual calculation mode
2. Press F9 and watch which areas take longest to update
3. Use Tools → Auditor to trace precedents/dependents
4. Look for volatile functions (NOW(), RAND(), etc.)
5. Check for array formulas (curly braces {})

Q: Can I set different calculation modes for different sheets?

A: OpenOffice Calc doesn't natively support per-sheet calculation modes, but you can:

• Move manual-calculation sheets to a separate file
• Use macros to temporarily change calculation mode when switching sheets
• Group sheets that should calculate together

Q: Why does my spreadsheet calculate slowly even in manual mode when I press F9?

A: Even in manual mode, pressing F9 triggers a full recalculation. If it's slow:

• Your spreadsheet may have inherent complexity that needs optimization
• Try Shift+F9 to calculate only the active sheet
• Check for external links that might be slow to update
• Look for very large arrays or complex matrix operations

Q: Is there a way to automatically switch between calculation modes based on file size?

A: Yes, you can create a macro that:

1. Checks the file size or number of formulas
2. Automatically switches to manual mode for large files
3. Provides a warning when opening files that might be slow

Here's a basic example:

Sub AutoSwitchCalcMode
    Dim doc as Object
    Dim sheets as Object
    Dim sheet as Object
    Dim cellCount as Long
    Dim formulaCount as Long
    Dim threshold as Long

    doc = ThisComponent
    sheets = doc.Sheets
    threshold = 10000 ' Set your threshold for cell count

    For Each sheet In sheets
        cellCount = cellCount + sheet.getCellRangeByPosition(0,0,sheet.Columns.getCount()-1,sheet.Rows.getCount()-1).getDataArray().Length
        ' Simple formula count (more accurate methods available)
        formulaCount = formulaCount + sheet.getCellRangeByPosition(0,0,sheet.Columns.getCount()-1,sheet.Rows.getCount()-1).queryContentCells(com.sun.star.sheet.CellFlags.FORMULA).getCount()
    Next

    If cellCount > threshold Or formulaCount > 1000 Then
        doc.CalculationMode = com.sun.star.sheet.CalculationMode.MANUAL
        MsgBox "Switched to manual calculation mode for better performance with this large spreadsheet." & Chr(10) & _
               "Press F9 to calculate when needed.", 64, "Performance Optimization"
    End If
End Sub

Conclusion

Controlling when and how OpenOffice Calc performs calculations can dramatically improve your productivity when working with large or complex spreadsheets. Start with the basic methods like switching to manual calculation mode, then explore more advanced techniques as needed. Remember that the best approach depends on your specific workbook structure and how you use it.

For most users, simply switching to manual calculation mode (Method 1) and pressing F9 when needed will provide immediate performance benefits. Power users working with very large models should explore the macro-based solutions and configuration adjustments for optimal results.

Regular maintenance of your spreadsheets—removing unused elements, optimizing formulas, and organizing data efficiently—will help prevent performance issues from developing in the first place.