How many times have you used the calculator on your Windows 7 machine? The answer would be - many.

On the whole, it doesn't look any different from the earlier calculators on Vista or XP. But what you didn't know is some cool new additions Microsoft has added, lying hidden in the menu.

Calculate the difference between dates.

What if you need to find out the number of days between two dates? Or even better - how many years, months,weeks and days between two dates? Windows 7 Calculator makes it easy. Just go to "View"->"Date Calculation". You can enter two dates and the calculator will give you the difference as either days or in "years/months/weeks/days" format. You can also find out the date that comes after adding or subtracting a specific number of days from a particular date.

A good use of this feature is to find out your exact age in years, months, weeks and days.

Unit Conversion

This feature lets you convert between all sorts of units. For instance, you can convert angles from degree to Radian, temperature in Celsius to Fahrenheit and a lot more. To access Unit conversion, go to "View"-> "Unit conversion". It includes almost every unit you can think of.

Now most of us would just use Google to do a conversion like "10.5 cm in inches". But you can now use the calculator when you are offline.

Mortgage calculation (or EMI in many countries)

If you are planning for a loan, you can use the calculator to find out how much you are going to end up paying the bank every month. You can access it from "View"->"Worksheets"->"Mortgage". Just input your loan amount, down-payment, tenure and the interest and you will get your mortgage figure.

Now to drag you into some hard realities, just enter this number into the normal calculator on the left, multiply it by 12 and multiply the result with your loan tenure. This is the total money you are going to pay to the bank. Now that's going to be considerable money compared to your loan amount. But relax, you need the loan and there's nothing much you can do about it :-)

Fuel Economy.

Fuel prices are continuously on the rise and high mileage vehicles have been topping the sales charts all over the world. So the next time you plan for that long trip, make sure to note down the distance you travelled and the litres or Gallons of fuel consumed. You can use the Fuel economy feature from "View"->"Worksheets"->"Fuel economy" to find out your car's performance.

So what do you think about these features? Please let me know as comments below.

Related: Did you know windows calculator had a bug all these years?