When we wrote about the amazing things Windows can do, one of the biggest surprises was the hidden features of the plain old calculator. It goes way beyond your basic functions of addition, subtraction, multiplication, and division. In fact, with the calculator’s different capabilities, you may find yourself putting away that old TI-68 calculator and using your spreadsheets less often.

We shouldn’t really be surprised that the Windows calculator can do so much. After all, it’s been with Windows since Windows 1.0, way back in 1985. There’s a good chance that this calculator is older than you!

Back then, it could only do so much. It was about as basic as a calculator could be. But, like you, it has matured over the years and developed new, complex abilities.

## The Windows Calculator

The Calculator app that comes with Windows 8.1 isn’t as robust as the calculator that came with Windows 8 and its predecessors. It’s limited in its capabilities.

There’s the **Standard** mode, which gives you basic math functions. Or the **Scientific** mode, which gives you the functions of a standard scientific calculator. Finally, the **Converter** mode, which allows you to do conversions between all sorts of units of measure, in ten different categories. Sure, those are handy, but that’s it. That’s the limits of the Windows 8.1 Calculator app.

With Windows 10, we see most of the functionality restored to this humble tool. It can do just about everything, to be sure, but it is lacking what is arguably the best feature of the Windows 8 calculator. Skip to number 9 to see that one. Still, with its sleek, pleasing to the eye design and a window that can be re-sized, the Windows 10 Calculator app is more calculator than most people ever need.

These 9 fascinating features are only found all together in the calculator program that came out of the box with Windows 7 and 8. If you’re on Windows 8.1 or 10, don’t worry! This article is still for you. You can use the Windows 7/8 calculator on these versions of Windows. It just takes a little set-up.

Keep reading to the end for a bonus that will make this calculator easier and faster to use. You’ll look like a math-magician when you start using it.

### Install calc.exe on Windows 8.1 or 10

Sergey Tkachenko of Winaero.com has packaged the old calc.exe so it’s easy for you to install on Windows 8.1 or 10. You can download the ready to install calc.exe from his site for free. He’s done a nice thing here, so you may want to tip him some coins. Now that we’ve made sure everyone has the classic calculator on their computer, let’s talk about using it.

### Opening Calculator

Opening calculator isn’t as limited as you might think. Because it’s such an integral part of Windows, there are many ways to bring it up. If your keyboard has a dedicated calculator button, just pressing that should launch it.

You could also open your start menu, and type **calc** in the **Run** box, then press your **Enter** key, or click on **OK**. Your **Start** menu will also have a shortcut.

If you’re pre-Windows 8.1, go to **All Programs > Accessories** and you’ll find calculator there. Use whichever way to open calculator that is most convenient for you.

### The Basic Calculator Layout

The basic calculator allows you to do all the basic math functions. Addition, subtraction, multiplication, and division are all there. There’s also the ability to calculate square root, store numbers in memory, get reciprocals, and work with percentages. Using it in this mode is great for tallying numbers or figuring out day-to-day math problems. But, you already knew that.

Even with just the basic calculator, there are things it can do that you might not know about. Or, if you do know about them, you might not know how to make use of them. Let’s carry on to take a look at all the things that the Windows calculator can do for you.

## The 9 Things You Didn’t Know Calculator Could Do

### 1. Group Digits with Commas

Under **View,** click on **Digit grouping** to get those nice commas every three digits. This makes it easier to see the difference between a million and a billion. It’s a pretty significant difference.

Now when you hear on the news that the government spent a billion dollars on something, you’ll know that’s a thousand million dollars. Seems like a lot more to you now, doesn’t it?

### 2. Keep a Record of What You’ve Entered

If you’re tallying numbers, you may want to turn on the history function. This makes it work like a desktop calculator with the built-in printer. You can see all the steps that you’ve done, in case you make a mistake somewhere. Turn on the history function by clicking on **View > History **or pressing the **Ctrl +**** H** keys together.

The up and down arrows in the top-right corner can be used to move back and forth between steps. Right-click on the calculator display and you’ll see the options to **Copy**, **Paste**, **Hide history**, and **Clear** history. You can also use the keyboard shortcut of **Ctrl** + **Shift** + **D **to delete the history.

Try clicking on **Edit > History > Copy history**. Now you can paste your calculation history into any other program. Maybe you want to show your math work at school, or use it in a spreadsheet.

### 3. Put a Frequently Used Number into Memory

Along the top row of the basic calculator, you’ll see the buttons **MC**, **MR**,** MS**,** M+**,** and M-**. Those are for memory functions. You might have used those in high school, but it’s possible you never have. They’re really useful. Let’s take a look at how to use them.

Let’s say you’re working with Pi. That’s 3.14 for most basic math. You might want to a go a few more digits and use 3.1416. That’s plenty of Pi for most people. Typing that in all the time is a pain, so add it to the calculator’s memory. Type it in, then press the save to memory button (**MS**). An uppercase M will show in the bottom-left corner of the display. Now when you want to use Pi again, you press the memory recall button (**MR**).

The add to memory button (**M+**) does something else. Let’s say you put the number 10 into memory. Then you do some math and the number in your display is 6. Pressing the **M+** button now will add 6 to your 10 making the number in memory 16. So, the next time you press the **MR** button, you’ll get 16.

The subtract from memory button (**M-**) does a similar thing. Let’s say you put the number 10 into memory. Then you do some math and the number in your display is 8. Pressing the **M-** button now will subtract 8 from your 10 making the number in memory 2. So, the next time you press the **MR** button, you’ll get 2.

If you no longer need a number in memory, press the memory clear button (**MC**) and whatever number was in memory will be deleted. The M in the bottom-left corner of the display will also disappear.

That’s more calculator functions than most people ever need. But of course, there’s more. Ready to do some science?

### 4. Perform Scientific Calculations

If you went into higher levels of math in high school, college, or university, you’ll recall the scientific calculator.

To switch to it, click on **View > Scientific Calculator** or press **Alt + 2**.

Now you’ll see a whole mess of buttons and functions. **Sin**, **Cos**, **Tan**, **Degrees**, **Radians**, **Grads**! What are they all for? Unless you’re a scientist, engineer, or student you’ll probably never use all these functions. But if you are one of those people, you’ll know what those keys are all about.

There are far too many to go into here, but if you’re interested, just watch the following video.

### 5. Help You with Programming

Where was this when I was in college? The programmer calculator is for, you guessed it, programmers and people working in computer science. To get to this mode, click on **View > Programmer Calculator** or press **Alt + 3**. Now you’ll see a calculator with some pretty odd looking features. There’s a second display below the regular display.

The top display can be switched between **Hexadecimal**, **Decimal**, **Octal**, and **Binary** number systems. If you’re looking to convert an ordinary number (decimal) to one of the other systems, this is where you would see those results.

The bottom display can be switched between the different word sizes of **Qword** (64 bits), **Dword** (32 bits), **Word** (16 bits) and **Byte** (8 bits). You probably recognize byte.

The middle column of buttons looks like txt speak. You’ll see things like **RoR**, **And**, **Rsh**. These are programming functions like logic gates and bit shifting. Computers make use of logic gates to make decisions and bit shifting for lots of other operations. You might use these functions if you’re doing anything with Arduino or Raspberry Pi boards. Micro-controller programming is often done at this level.

Knowing these things now, you can see how this would be a valuable calculator to a programmer. Maybe at some point you’ll want to learn more about programming, and now you’ll know where to find a handy calculator to help you along.

### 6. Use for Statistical Analysis

The statistics calculator will be of special interest to anyone learning statistics in college or if you work in a field that requires some statistical analysis. One use that you might find handy is the average function. You can enter a long list of numbers, click one button, and get the average of them all. Let’s look at how to do that.

Enter your first number. Let’s say it’s 20. Now click on the add button *(figure 1, below)*. This adds the number to a list. You’ll now see 20 at the top of the calculator display. Now add 30, then 40, then 50. You’ll see those numbers all listed in the display. Click on the average of the values button *(fig. 2)*. Bam, there’s your average and it is 35.

The other statistics buttons are as follows: average of the square of values *(fig. 3)*, sum of the values *(fig. 4)*, sum of the square of the values *(fig. 5)*, standard deviation *(fig. 6)*, and standard deviation of population *(fig. 7)*. All these tools are basic to statistical mathematics.

Well, that’s great that you’ve got a statistics, programming, scientific, and basic calendar all in one. Yet, there is still even more you can do.

### 7. Do Math with Dates

For planning events or anything date-related, the date calculation function is for you. You can calculate the difference between two dates. If you were born on January 1st, 1970, this tool will let you know that you were 16,825 days old as of January 25th, 2016. Not a terribly useful fact, but you could figure out how many days until that wedding or vacation, too.

You can also add or subtract days from a specific date. If you have a 6 month deadline, this tool will help you figure out what is that date. Just add 6 months to today’s date, and write that date in your planner. Or, if you need to figure out if you’re still within your 180 day warranty, just add 180 days to the date on your receipt and you’ll know.

### 8. Convert Units of Measurement

Planning a trip to Canada? You may want to use the unit conversion tool in the calculator. When you see those signs on the highway reading 100 km/h speed limit, don’t get too excited! The calculator will tell you that’s only 62 mph. Or, if you think the gas there is cheap at 89 cents CDN, that’s really 3.79 times 89 cents per liter – or $3.37 CDN per gallon. Unfortunately, it doesn’t do exchange rates.

The unit conversion tool can handle angle, area, energy, length, power, pressure, temperature, time, velocity, volume, and weight and mass conversions. It will do several different units of measurement within each of those categories.

### 9. Replace Your Spreadsheets with Built-in Worksheets

The worksheets built into the calculator are the tools that could mean the most to you. They are the kind of forms where you can fill in one spot and get the answers you need in other spots, instantly. You could create spreadsheets to do the same things, but why re-create what’s already there and working well?

With the worksheets available in calculator, you can quickly get answers about mortgages, leases, and gas mileage. These are some of the most important calculations you will ever make. As an example, let’s take a look at how you can figure out how much home you can afford with the mortgage worksheet.

Pop open calculator, click on **View**, go down to **Worksheets** and click on **Mortgage**. A clear and simple form will appear to the right of the calculator.

With the mortgage worksheet, you can quickly figure out what your monthly payment would be, how much of a down payment you’ll need to save up, the highest price you can afford to pay, and how many years it will take to pay it off. This worksheet lets you quickly try out different scenarios and see what’s possible for you.

Sure, there are a million mortgage calculators online. But they all have advertising and stuff to distract you from focusing on the most important purchase you’ll ever make. With the mortgage worksheet, there’s no waiting for pages to load, or talking to mortgage salespeople. How convenient is that?

Remember, the calculator worksheets can help you figure out some other important life numbers. Use the **Leasing** worksheet before signing off on leasing that new hybrid car. You could avoid some real nasty surprises. When you get the car, use the **Mileage** worksheet to see just how many gallons that new hybrid is saving you. This calculator could literally save you thousands of dollars.

### Bonus Feature – Calculator Keyboard Shortcuts

The fun doesn’t stop, folks. Just as regular Windows keyboard shortcuts increase your productivity and make you look like a star in the office, calculator has its own keyboard shortcuts. Just follow this link to Microsoft’s Windows Calculator Keyboard Shortcuts. Start using them and people might think you’re some sort of accountant or rocket scientist. Note that these shortcuts are intended for the Windows 7/8 calculator we’ve been talking about all along.

## What Else is Windows Hiding in its Common Tools?

The calculator isn’t the only tool like this in Windows. Sometimes, it’s easy to overlook the little things and think Windows doesn’t do much for you. Poke around a bit and you may find that there are many amazing things you can do with Windows that you never thought possible.

**Now that you know all that this overlooked Windows tool can do, what will you use it for? Will it replace some of your spreadsheet tools? Can you use it for your school or work?** Let us know. We’re interested to see just how much this amazing calculator can do for you.

Image Credits: Windows 10 Calculator App – Scientific Mode, via Microsoft, Texas Instruments TI 68 Calculator, via Wikimedia, Windows 1.0 Calculator, via Toasty Tech.

In the statistics calculator, figure 6 is population standard deviation and figure 7 is the sample standard deviation