How to Use the iPhone Calculator Extended
The Calculator app is probably one of the most used Apple apps on the iPhone, but I meet people all the time who don’t know all the little tricks to use it more effectively. You may know most of them, but there is a chance that you don’t know all of them or have simply forgotten about them.
What a “hidden trick”is to some people may be obvious to others, so feel free to skip the ones you already know in the list below. This review is for everyone from the complete newbie to smartphones to those who have owned an iPhone since the iPhone was a thing, and even professional mathematicians. For the most part, I’ve sorted it from the simplest, most intuitive actions to the more complex ones, so skip those if you need to.
Open calculator
So, it’s pretty obvious…or isn’t it? Yes, you can tap the Calculator app icon on the home screen, but there are other ways to open the calculator. Here are just a few of the ways you can do this:
- Touch its icon on the home screen.
- Tap its icon in the App Library. (Only for iOS 14 and later.)
- Tap its icon in Search.
- Tap its icon in the Control Center.
- Say or type “Calculator”to Siri or Hey Siri.
- Double or triple-tap the back of iPhone. (Only for iOS 14 and later – see Tip 16 below.)
- Open it from a custom shortcut via the Home or Today widget, Shortcuts app, Siri or Hey Siri, Search, or double or triple tap the back of your iPhone.
- Let it open on its own using various shortcut automation scripts. (See Tip 17 below.)
Unlock Scientific Calculator
You most likely stumbled upon this by accident, but I know some people who have never turned their iPhone on its side, except to watch Netflix or Hulu. So rotate your iPhone to landscape orientation and the calculator will automatically change from a standard calculator (for basic arithmetic calculations) to a scientific calculator (for exponential, logarithmic and trigonometric functions).
You will find more advanced options such as cosine (cos), tangent (tan), square root (v), natural logarithm (ln) and pseudo-random number generator (Rand) which are most useful for science, engineering and advanced mathematics.
Erase the numbers you just entered
If you meant to enter 523 instead of 532, “shake to undo”won’t delete your last few digits because that feature is disabled in the calculator. But there is an easier way to delete the entered numbers. Just swipe left or right across the number field, or really anywhere above the keys, and the last digit will be deleted. If you need to get rid of two, swipe again. Three? You receive a picture. If you need to redo the entire number, see the next tip.
Erase the integers you just entered
Whenever you enter an integer incorrectly, there is a very quick way to correct the mistake. Again, “Shake to Undo”won’t work since it’s disabled in the calculator. Instead, you can simply clear the display with the “C”key, which stands for Clear. This won’t erase all your progress, just the last entry. So if you entered 1242 x 324 but meant 1242 x 423, press “C”then enter 423 and continue the calculation.
start over
If you need to start from scratch, you can use the “AC”key, which stands for “Clear All”. If you don’t see the “AC”button, it’s because it only appears after you’ve cleared the display, so you’ll have to press “C”first before “AC”appears in its place. Touch this to start over. (Note that forcing Calculator to close won’t work, as it will still remember your last result.)
: copy and paste numbers
Apple’s help pages only mention one way to copy and paste numbers into the calculator, but there are actually many different ways to do it. If you’re trying to paste a number, you’ll only see the “Paste”option if you already have a number saved on your clipboard.
- Press and hold the currently displayed number. Click “Copy”on the menu to copy the number, or click “Paste”if the clipboard has the number you want to use in the calculation.
- Double-tap the currently displayed number. Click “Copy”on the menu to copy the number, or click “Paste”if the clipboard has the number you want to use in the calculation.
- Touch the display with three fingers. Tap the Copy icon (middle button) to copy the currently displayed number, or tap the Paste icon (to the right of Copy) if you have a number saved on the clipboard that you want to use in calculations. (Only for iOS 13 and later.)
- Pinch the display with three fingers. This will copy the currently displayed number.
- Touch the display with three fingers and move them apart. Think of it as the opposite of a three-finger pinch. This will insert the currently displayed number. (Only for iOS 13 and later.)
Copy the last result
If you’re still in the Calculator app and need to copy your current result, you can simply use one of the options above. However, if you’re no longer in the Calculator app, there are a few more ways to do so.
- Swipe to open the Control Center, then press and hold the calculator icon.
- Press and hold the Calculator app icon on the home screen.
- Press and hold the Calculator app icon in the App Library.
- Press and hold the Calculator app icon in search.
Either way, you’ll see an option to “Copy Last Result”and it will list the last result so you know it’s correct. Your latest result should appear even after you force close the calculator.
Home screen (left), Control Center (middle), and Search (right).
Perform calculations in search
Now that we’ve mentioned Search, it’s nice to know that you can do math calculations right from it, instead of having to open the Calculator app at all. To open search, swipe down from the home screen, or open Today view by swiping to the far left of the home screen or lock screen.
Then enter an equation or formula. A field with your result will appear right below the search field. Touch this and you will go straight to the calculator with the result already entered if you want to continue your math problem there.
You won’t be able to perform complex calculations as the keys restrict your keyboard, but this can be solved by installing a keyboard with advanced calculator features. Third-party keyboards that you can use in your search include Numboard – Scientific Keyboard, Calculation Keyboard, Calculator Keyboard, Calculator Keyboard – Faster, and SciKey – Scientific Keyboard. However, not all math operators, symbols, variables, constants, and functions are supported in Search, so you may still need to open Calculator if you find that they don’t work.
Let Siri do all the work for you
Whether you’re using Type to Siri, Hey Siri, or a Siri keyboard shortcut, you can ask it to do your calculations in some cases without even lifting a finger. Just say something like:
- “What is 74 times 14?”
- “What is 28 percent of 225?”
- “What is a third of 456?”
If you try to ask it more complex tasks, like algebraic expressions, Siri won’t use the calculator to get the results. Instead, it will use something like WolframAlpha or Safari to get answers or links to possible answers. For example, “What is 15% of 45% of 1.4?”This pulls up WolframAlpha for me with a score of 0.0945.
Rethink how you use buttons
When using a calculator, most of you will be entering a number, pressing a character, entering a few more numbers, pressing another character, and so on. But this is not the only way to do it. Let’s say you want to convert % to decimal. Typically you enter a number and then press the % key. However, you can also press and hold the % key first, then enter a number and release the % key to get the same result. Try other buttons and symbols and you will find that it works faster in some cases.
Click “Second”to find more options
If you’re new to scientific calculators, this might come in handy. Since all the options won’t fit on the keyboard, you can press the “second”key to change some of the other keys. For example, sin becomes sin-1, ln becomes logY, eX becomes yX, and so on.
Get a random number
The scientific calculator has a “RANDOM”key, which is a random number generator function that produces a number between zero (0) and one (1). More precisely, it is a pseudo-random number because the software cannot randomly generate the results of unpredictable natural phenomena, such as throwing dice or measuring atmospheric noise. With it, you can perform calculations, for example, emulate the throwing of dice.
Make your iPhone speak numbers
If you want to know how to pronounce a number, you can have your iPhone say it to you. In the Calculator app, you can press and hold the current number or double-tap it, then select Speak from the menu to hear it pronounced like words, or Speak to have each number and symbol spoken separately in order. If you don’t see these menu options, enable them in the Accessibility settings in Settings:
- Spoken Content -> Speak Selected (iOS 13 and later)
- Speech -> Speak Selection (iOS 12 and later)
Change the color of the calculator
There aren’t many ways to change the colors of the calculator, but that doesn’t mean it’s impossible. Dark Mode in iOS 13 and later doesn’t affect it because the calculator already has a dark theme and Smart Invert doesn’t do anything with the theme either. However, you can use the classic invert and color filters to make everything look the way you want. For Classic Invert in Accessibility settings go to:
- Text Display and Size -> Classic Invert (iOS 13 and later)
- Display Adaptation –> Invert Colors –> Classic Invert (iOS 12 and later)
For color filters in Accessibility settings, go to:
- Display & Text Size -> Color Filters (iOS 13 and later)
- Display adaptation -> Color filters (iOS 12 and older)
Classic Invert changes the look to an inverted color scheme, while Color Filters gives you plenty of options, from grayscale to red/green, green/red and blue/yellow, and you can even tint your screen with any hue. To make it more useful, add the classic invert and color filters to the “Accessibility Shortcut”in the “Accessibility”settings. Then just triple-click the side or home button to activate it when it’s in Calculator, and then do it again when you exit Calculator.
Classical inversion (left) and grayscale (right).
Make a shortcut to automatically change calculator colors
If you like the Shortcuts app, you can use it in iOS 14 and later to create an automation that will change the calculator’s color scheme every time you open the app, then return it to normal whenever the app closes. I won’t describe the process here, but you can see how to build an automation in our complete guide. Below you can see classic inversion in action (left) and grayscale (right).
Open the calculator by tapping on your iPhone
Apple introduced Back Tap in iOS 14, an accessibility feature that lets you double or triple tap the back of your iPhone 8 or later to trigger an action of your choice. For it to open the Calculator, you must create a new shortcut and add one action: “Open App”, where “Calculator”would be that app. Then go to “Settings”-> “Accessibility”-> “Touch Screen”-> “Back”. Select “Double tap”or “Triple tap”and select the shortcut you created. Now whenever you touch your iPhone, the calculator opens.
Set up extended shortcuts
While we’re on the subject of labels, this brings us to our final piece of advice. The Shortcuts app will let you create just about any trigger action script, automation, or task, and the calculator has several actions you can include in your workflows – ten to be exact. I won’t go into the details of how to use each one, as each could become an entire article, but I’ll include their descriptions.
- Compute: Performs a numeric operation on the input and returns the result. (Input: Boolean, Workout Sample, Text, File Size, Time Interval, Date, Blood Pressure, Number, Health Sample, Current Amount, Measurement – Results: Numbers)
- Calculate Statistics: Calculates statistics on the numbers provided as input. (Input: booleans, workout samples, text, file sizes, timeslots, dates, blood pressure, numbers, health samples, current counts, measurements – results: numbers)
- Evaluate Expression: Evaluates the mathematical expression in the given input string and outputs the result as a number. (Input: text – output: number)
- Count: Counts the number of elements, characters, words, sentences, or lines passed as input. (Input: anything, text – result: number – Note: this is the same as the graph in Sesame Street, but instead of a vampire, it’s a shortcut action.)
- Format File Size: Formats the file size into text. (Input: file sizes, numbers (file size from another activity, or number of bytes) – Result: text – Note: 1000 bytes are displayed as 1 KB.)
- Number Format: Formats a number into text. (Input: booleans, numbers – result: text)
- Get numbers from input: Returns numbers from the output of the previous action. (Input: booleans, workout examples, text, file sizes, timeslots, dates, blood pressure, numbers, health samples, currency amounts, measurements – result: numbers)
- Number: Passes a number to the next action. (Result: number)
- Random Number: Passes a random number between the given minimum and maximum to the next action. The minimum and maximum numbers are included as possible results. (Result: number)
- Round Number: Rounds the numbers passed into the action. (Input: numbers – Result: numbers)