Memory Operations

KCalc supports the memory operations given by standard calculators plus six slots to hold constants.

Standard Memory Operations

KCalc can remember results of operations for you, and re-use them in later calculations. You can access these functions via several buttons labeled MR, MS, M+ and MC.


The MS button stores the currently displayed result in memory.


The M+ button adds the current result to the one in memory. So, if you had stored a 20, and the current result is a 5, your memory would contain 25 when you press it. If the memory is empty, it acts like MS and simply stores the result.


The MR button gets the value stored in memory and puts it in the display.


The MC button clears the memory.

If a value is stored in memory a M will appear in the status bar, next to the calculator mode indicator


The six constants buttons C1 to C6 will only be visible after activating the item Constants Buttons in the menu Settings of the menu bar. They are available in Science mode and Statistics mode

To see the value stored in each constant hover the button with the mouse pointer.

To store the number shown in the KCalc display in one of the six constants, first press Shift followed by the desired button key C1 up to C6.

To use the value stored in any of the constants in a calculation, just press the desired button (C1 to C6), and the corresponding number will appear in the display.

It is possible to change the label of the constants button to make it easier to remember which button holds which constant. Click with the right mouse button on one of the buttons C1 to C6. A popup menu appears, in which you select Set Name.

There are many (mostly physical) predefined constants, which can be put on any of the six buttons C1 - C6 by selecting the desired constant in the popup menu that appears after right clicking on one of the constant buttons and selecting Choose from List. Though the predefined constants can also be accessed via the Constants in the menu bar, storing it on a constants button is very handy, if the number is used frequently.