Formulas can be viewed as Math equations, using standard Math notation  like you learned at school.
When the 'Math Equation Viewer' is on:
 Formulas are automatically displayed in Math notation.
 References (cells) can be displayed as their address, their name (if they're a named range), their value or the value in the cell to the left of them.
 If named ranges or 'cells to the left' contain the name of a Greek letter, such as alpha, beta, pi etc. then the equation will display the Greek symbol instead.
 Greek letters can also be written with a leading '\' eg: \pi, \alpha. In fact, if a cell's value is a sentence that includes Greek letters, then the letter names MUST be preceeded with '\', otherwise they will be ignored.
 Copy or save the current equation as an image by clicking the 'Copy' or 'Save' buttons on the menu above the equation.
 When editing a formula, the Math viewer highlights ranges in same colors as formulabar.
 Save (or copy) any equation or shape on a worksheet by rightclicking it, then clicking 'FormulaDesk > Copy as image' or 'FormulaDesk > Save as image' on the popup menu.
Add live (autoupdating) equations to the worksheet
Add the equation displayed in the Math Equation viewer to the current worksheet. 'Live' equations will autoupdate when the cell's formula changes.
To add a 'Live' equation, in the Math Equation viewer
 Click the 'Add to sheet (live)' ...or 'Add to sheet (static)' to add a nonautoupdating equation.
 For 'Live' equations, Click 'FormulaDesk > Go to cell' on the rightclick menu to go to the source cell which has the formula on which the Live equation is based.
Quickly add Greek letters and subscripts
 To enter Greek letters into cells, type their name (eg: pi, alpha, beta), or if the cell contains more text in addition to the Greek letter, then prepend the Greek letter name with '\' (eg: \pi, \alpha, \beta).
 To enter subscripts, use an underscore (eg: d_x).
 Select the cells.
 Rightclick the selected cells. In the popup menu, click 'FormulaDesk > Convert text to Greek letters and subscripts'
 A form will open, select your options then apply.
 The selected cells will be transformed!
Save (or copy) shape and equations as images
 Select the shape or equation.
 Rightclick the selected cells. In the popup menu, click 'FormulaDesk > Copy as image' (or 'Save as image').
Press and release CTRL+TAB to swicth between current sheet and previous one. Alternatively, pressing CTRL+TAB then releasing TAB but keeping CTRL pressed shows a popup navigation screen which allows you to switch between recentlyviewed sheets quickly, even across workbooks. Keep CTRL pressed while using this screen. Releasing the CTRL key hides the screen and navigates to the currently selected sheet. Use TAB or DOWN_ARROW to move down and SHIFT+TAB or UP_ARROW to move up. Use LEFT_ARROW and RIGHT_ARROW to move left and right.
Click the 'Back' button to go back to previous cell or select a previous cell from the dropdown. Alternatively, press ALT+LEFT to go back one or ALT+RIGHT to go forward one.
See any part of your spreadsheet in it's own floating window. It will always show a live view, displaying updates as you edit another part of the spreadsheet.
You can create periscopes for ranges of cells and for charts.
Note: The periscope is viewonly. You can't interact with or edit the contents of the periscope window.
 Rightclick a selected range of cells or chart.
 Click 'FormulaDesk' > 'Create Periscope' on the popup menu.
Excel only allows you to freeze columns and rows on the left. With FormulaDesk you can now freeze any combination of columns and rows and make them appear on the righthand side of the worksheet. Their values update in realtime as you make changes to your spreadsheet.
 Select the column(s) or row(s) to freeze by clicking the column or row headers (hold down the CTRL button to select noncontiguous columns or rows).
 Rightclick the selected column.
 Click 'Freeze columns' on the popup menu.
 Add more columns at any time by following the same procedure above  they will be added to the frozen collection.
 To close the frozen column, hover over the frozen columns and a close button will appear above them, at the top right.
FormulaDesk has a profiler which times the calculation speeds of the cells in your file. This is a performance tools that shows you exactly where your spreadsheet is slow and gives you the information you need to make your spreadsheet faster.
 Calculation times.
 Volatile cells  get a full list of all volatile cells and their calculation times.
 Mini barcharts make comparison easy.
 Hovering over an address displays the underlying formula.
When 'Show Precedents' and/or 'Show Descendents' is turned on, as you click on different cells, their precedents/descendents are shown in realtime.
 Live preview: hover over an arrow to display the precedent cell and its surrounding cells. This also works for precedents on other sheets (or scrolled off the screen)  no need to switch to the sheet to inspect the value.
 Choose to view direct precedents only, or all levels at once.
 Display arrows and/or highlight the precedents a different color.
 Display precedents/descendents across all sheets, or limit to just the current sheet.
 Pause the 'Live View' mode to stop automatically displaying precedents when other cells are clicked.
See intermediate values in a single glance. A staggered view enables quicker understanding ie: no need to continually click the 'Evaluate formula' button multiple times to determine how a value is calculated anymore.
 Hover over parts of a formula to get further information.
 Write your formulas in the single line above the staggered view.
FormulaDesk pinpoints exactly where the error is. Normally, you have no idea exactly where or what the error is.
 The 'deepest' error is usually the rootcause of 'upstream' errors.
 Hovering over an error displays more information about the problem.
Oneclick to break complex formulas into small steps, which are then written to a new sheet, allowing you to work through the individual steps and gain a thorough understanding of the formula.
Turn on the crosshairs feature to easily track the active cell. Easily see which cells are in the same column and row.
Easily select and deselect multiple cells and ranges by clicking the 'Easy Select' button to turn 'Easy Selection mode' on, then start making your selections. When you're finished making selections, click the 'Easy Select' button again to turn 'Easy Selection mode' off again.
No need to hold down the CTRL key while selecting  just click and drag to select/deselect what you want.
The FormulaDesk profiler enables you to profile (time the calculation speeds) of all volatile cells  as well as their dependents (ie: cells that have a volatile formula, such as NOW(), as well as cells that reference that cell, and are therefore indirectly volatile).
Excel files can grow big due to many blank cells. The 'Trim Bloated Workbook' feature can find these blank rows and columns for you, and gives you the option to delete them too.
If you receive a Too many different cell formats error in Excel, the 'Trim Bloated Workbook' features can tell you which custom styles in your spreadsheet are unused and can be deleted.
If your workbook calculation mode is set to manual then that setting gets saved when you save the file. This means that when the file is opened by you or anyone else it will be in manual calculation mode. Sometimes that's what you want, but ususally it isn't. Also, when you open a file from someone else, do you remember to check the calculation mode every time, in case the other person saved it in manual mode?
FormulaDesk can alert you when you try to save a file with manual calculation mode on, or when you open a file that has manual calculation mode on.
Now you can easily create a formula by first splitting it between many cells, then combine them into a single megaformula.
This makes it possible to compose formulas from small understandable subformulas.
When you're finished, copy the formula text from top line of the editor.
Easily resize an array formula by selecting the range you want to resize it to, then rightclick the selection and click the 'Resize array' item on the context (popup) menu, or the 'Resize array' on the top menu.
Easily rightsize an array formula to exactly match it's dimensions by selecting a cell containing the array formula, then rightclick the selection and click the 'Rightsize array' item on the context (popup) menu, or the 'Rightsize array' on the top menu.
Use Workbook Detective searches all of your sheets, even the hidden ones, to find and list all:
 Comments
 Formula Errors
 Usages of data connections
 Invalid data (fails validation rules)

Links to external workbooks, where they are used in:
 Cell formulas
 Charts
 Names
If you keep pressing special keys by mistake, you can now disable them (just inside Excel) so that they never bother you again while you're working in Excel.
You can disable and ignore the following keys:
 F1
 Insert
 NumLock
 ScrollLock
 CapsLock
Now you can easily find formulas that contain a specific pattern. For example, say you want to find all formulas that contain the SUM function with three arguments anywhere in the formula Example: SUM(1, 2, 3)
It will find 'patterns' even when they are nested deeep inside a formula, no matter how complex the formula is.
The process of 'improving' or 'cleaning up' your formulas is technically known as Refactoring, and is usually applied to sourcecode in software programs. Now, you can refactor your Excel spreadsheets!
You can define the 'pattern' with placeholders for the variable content eg: SUM({a}, {b}, {c})
This pattern will be found in the following formulas:

=SUM(11, 22, 33)
One pattern found. Variables: {a}: 11
 {b}: 22
 {c}: 33

=A3 + G6  SUM(H7, F1, 777) + 888
One pattern found. Variables: {a}: H7
 {b}: F1
 {c}: 777

=7 + SUM(11, IF(1 > 2, SUM(A1, B3, C1), 22), 33)
Two patterns found:
First pattern found. Variables: {a}: 11
 {b}: IF(1 > 2, SUM(A1, B3, C1), 22)
 {c}: 33
Second pattern found. Variables: {a}: A1
 {b}: B3
 {c}: C1
Once cells with matching formulas are found, then you can choose to replace the pattern with another pattern. Replacement template text can use the variables defined in the 'find pattern' Eg: Using the example pattern above SUM({a}, {b}, {c}, we can write the replacement template text like this: ({a} + {b} + {c}). If we run this replacement on the formulas above we get the following outputs:
 =SUM(11, 22, 33)
gets transformed into: =(11 + 22 + 33)
 =A3 + G6  SUM(H7, F1, 777) + 888
gets transformed into: =A3 + G6  (H7 + F1 + 777) + 888
 =7 + SUM(11, IF(1 > 2, SUM(A1, B3, C1), 22), 33)
gets transformed into: =7 + (11 + IF(1 > 2, (A1 + B3 + C1), 22) + 33)
This enables you to quickly and easily replace references (cell addresses) in formulas.
Specify the reference (use wildcards if you need to ('*' for multiple characters and '?' for single characters)
Eg:
 Sheet3!B45 (finds all formulas with this exact reference)
 Sheet3!B* (finds all formulas with references to any cell in column B of Sheet3)
 Sheet3!* (finds all formulas with references to any cell on Sheet3)
Specify the replacement as exact text, or using the following variables (note the use of curly braces!):
 {Ref.Sheet} This is the name of the sheet in the discovered reference (if one was specified in the formula) including the '!'. If the discovered reference didn't include a sheet name, then this variable will be blank.
 {Ref.Address} This is the address part of the discovered reference Eg: A5, B3
Examples:
 To replace all references to any cells on 'Sheet2' with the same cell address on the 'Totals' sheet:
 Find pattern: Sheet2!*
 Replacement pattern: Totals!{Ref.Address}
 To replace all references to all sheets whose name starts with Sheet (eg: Sheet1, Sheet2, Sheet3) with NewSheet1, NewSheet2, NewSheet3 etc:
 Find pattern: Sheet*!*
 Replacement pattern: New{Ref.Sheet}{Ref.Address}
Replaces the format items in the specified string with the string representation of the specified arguments.
Write this: =FD.Text.ToStringFormat("Hello {0}. How is the weather in {1}?", "Bob", "New York")Instead of this: ="Hello" & "Bob" & ". How is the weather in " & "New York?"