The fastest way to reset your calculator

Most calculators have a Clear button (labeled C or AC) that wipes the display and any stored numbers. Press it once to clear the current calculation. On phones and computers, the same button usually clears everything you've entered so far, letting you start a new problem from zero.

If your calculator has two clear options — C and AC — C clears only the current entry, while AC (All Clear) resets the entire calculator memory. For everyday math, the C button is usually what you need. Use AC if you want to make sure nothing from a previous calculation is still stored.

On a smartphone or computer, the clear button works the same way. Open your calculator app, and look for a C or AC button. One tap removes what you just typed. If you can't find a dedicated button, try swiping left or right on the display — many phone calculators respond to swipe gestures to clear the screen.

Key Takeaways

  • The C button clears only your current entry, while AC clears the entire calculator and any stored values.
  • On most phones, you can swipe left or right on the display to clear the screen instead of tapping a button.
  • Scientific calculators may have additional memory buttons (M+, M-, MR) that store numbers separately from the main display.
  • If your calculator is frozen or not responding, a full reset (usually holding the power button for 10 seconds) can restore normal function.

Clearing memory on scientific and graphing calculators

Scientific calculators often store numbers in separate memory slots using buttons labeled M+, M−, MR (Memory Recall), and MC (Memory Clear). If you've used these buttons during a calculation, pressing MC clears only the stored memory — it does not clear the display. Press C or AC afterward to clear what you see on screen.

Graphing calculators like the TI-84 work differently. Press 2nd, then + (MEM), then select Delete or Clear All to wipe stored variables and programs. This is useful if your calculator is running slowly or if you want to remove old data before starting fresh. A simpler option is to press 2nd, then 7 (Reset), which returns the calculator to factory settings.

What to do if your calculator won't clear

If pressing C or AC does nothing, the calculator may be frozen. Try removing the batteries (if it uses them) and waiting 30 seconds before reinserting them. This forces a soft reset without erasing your stored data. For solar calculators or those with a built-in battery, hold down the power button for 10 to 15 seconds until the display goes blank, then release.

If the calculator still does not respond, check whether the battery is dead. A weak battery can cause the display to freeze or show incorrect results. Replace it with a fresh one of the same type and size. If you have a graphing calculator and nothing else works, consult the manual for a hard reset procedure — this varies by model and may erase all your stored programs and data.

Clearing calculations on your phone or computer

On an iPhone, open the Calculator app and swipe left across the display to clear it. On Android, the method depends on your phone's calculator app — some have a dedicated C button, while others require you to tap the delete icon (usually a backspace arrow) or swipe to clear. Check your app's help menu if you're unsure.

On Windows, the Calculator app has a C button in the top left. On Mac, the Calculator app uses the same C button. Both work the same way as a physical calculator. If you're using a web-based calculator in your browser, look for a Reset or Clear button near the display, or simply refresh the page to start over.

Resetting a calculator app to factory settings

If you want to remove all stored data from a calculator app on your phone, you may need to uninstall and reinstall it. On iPhone, press and hold the Calculator app icon, select Remove App, then Delete App. On Android, open Settings, go to Apps, find Calculator, and tap Uninstall. Reinstalling the app from the App Store or Google Play restores it to its original state.

For computer calculator apps, the process is similar. On Windows, open Settings, go to Apps, find Calculator, and select Uninstall. On Mac, drag the Calculator app to the Trash, then empty the Trash. Reinstalling from the App Store or Microsoft Store gives you a fresh version with no stored data.

Understanding what gets cleared and what doesn't

When you press C or AC, you clear the display and the current calculation. You do not erase any numbers you may have written down elsewhere or any data stored in the calculator's memory slots (M+, M−, etc.). If you want a completely blank slate, press AC first, then press MC (Memory Clear) if your calculator has that button.

On graphing calculators, pressing C clears the display but leaves your stored variables and programs intact. If you want to remove those as well, use the Delete or Clear All function in the memory menu. This is important to know if you're sharing a calculator with someone else or if you want to make sure old data does not interfere with a new calculation.

Frequently Asked Questions

What's the difference between C and AC on a calculator?

C clears only the number you just typed or the result on the display. AC (All Clear) clears everything — the display, any pending operations, and sometimes the memory. If you made a mistake in your current entry, C is usually enough. Use AC if you want to start a completely new calculation.

How do I clear the memory on my calculator?

Look for a button labeled MC (Memory Clear) or MEM. Press it to erase any numbers stored in the calculator's memory slots. This does not clear the display — press C or AC separately to clear what you see on screen. On graphing calculators, use the memory menu (usually accessed through 2nd + a number key) to delete stored variables.

Why is my calculator frozen and not responding to the clear button?

The calculator may have a dead or weak battery. Try replacing the battery with a fresh one. If it still does not respond, remove the battery for 30 seconds and reinsert it to force a soft reset. For solar calculators, hold the power button for 10 to 15 seconds. If nothing works, consult your calculator's manual for a hard reset procedure.

Can I clear my calculator without losing saved data?

Yes. Pressing C clears only the current display and calculation, not any numbers stored in memory slots. If you want to keep stored data but clear the display, press C instead of AC. On graphing calculators, pressing C clears the screen but leaves your programs and variables intact — use the Delete function in the memory menu only if you want to erase those.

How do I reset a calculator app on my phone?

Swipe left or right on the display to clear the current calculation. To remove all data from the app, uninstall it and reinstall it from the App Store (iPhone) or Google Play (Android). This restores the app to its original state without any stored data or history.