Calculator memory button reference
| Key | Typical meaning | Typical action |
|---|---|---|
| MC | Memory Clear | Reset memory to zero |
| MR | Memory Recall | Bring memory value to display |
| MS | Memory Store | Replace memory with displayed value |
| M+ | Memory Plus | Add displayed value to memory |
| M− | Memory Minus | Subtract displayed value from memory |
| MRC | Memory Recall/Clear | Combined recall/clear on some models |
Labels can vary. RM may be used instead of MR, and CM instead of MC on some calculators.
How memory differs from normal arithmetic
The normal + and − keys change the expression you are calculating. Memory keys change a second stored value. This lets you finish one calculation, save or accumulate its result in memory, clear the display, calculate something else, then recall the stored number when needed.
Running-total example with M+
To total 125.40, 89.95 and 42.10 without building one long expression: press MC, enter 125.40 and M+, enter 89.95 and M+, enter 42.10 and M+, then press MR. The memory total is 257.45.
Using M− for deductions
Suppose memory contains 500 and you need to deduct 75 and 20. Enter 75 and press M−, then enter 20 and press M−. Memory is now 405. Press MR to recall it.
What the M indicator means
Many calculators show a small M icon when memory contains a value. On the Office Calculator homepage, an M indicator appears while the memory value is non-zero. Pressing MC clears the stored value and removes that indicator.
Memory versus history or calculation tape
Memory is fast but usually stores only one value. A calculator history or tape records multiple completed calculations, making it easier to audit what happened. Use memory for a temporary number; use history when you want a visible sequence.
Frequently asked questions
What does M stand for on a calculator?
M refers to calculator memory, a stored value separate from the current display.
Does MC clear the whole calculator?
No. MC normally clears only the memory register. C or AC clears the current calculation/display.
Can memory hold a negative number?
Yes on many calculators. M− can reduce memory below zero.
Is MRC the same as MR?
Not exactly. MRC is a combined memory recall/clear key on some models, while MR only recalls memory.
Open the matching OfficeCalculator.Net tool and test the examples with your own values.