how do you turn a casio calculator off

Quick answer

On most Casio scientific calculators, you turn the calculator off by pressing SHIFT and then the key with OFF printed above it (usually AC or ON). If your model does not show an OFF function, it usually shuts down automatically after a few minutes of inactivity.

• Look above the keys for small secondary labels like OFF.
• Press SHIFT first to activate that top label.
• Press the base key under OFF (often AC).
• If nothing happens, check battery condition and stuck keys.

Why turning off a Casio can feel confusing

Casio calculators often place the OFF command as a secondary function instead of a dedicated button. That means the word “OFF” is printed above a different key in tiny text. If you are used to calculators with a clear POWER switch, this design can be easy to miss.

In short: your calculator probably does have a power-off function; it is just hidden behind SHIFT (or 2nd function on some models).

How to turn off each common Casio type

Scientific models (fx-82, fx-300, fx-991 and similar)

1. Finish any active input by pressing AC once.
2. Find the small OFF label above a key (commonly AC).
3. Press SHIFT.
4. Press that key (for many models this is AC).

The display should go blank immediately. To turn back on, press ON or AC, depending on model.

ClassWiz models (EX/CW series)

ClassWiz units typically follow the same idea: SHIFT + OFF (where OFF is printed above another key). The keyboard layout is cleaner, but the same secondary-function logic applies.

• If you are in a menu, exit to the home screen first.
• Then press SHIFT and the key marked with OFF.

Graphing models (fx-9750G / fx-9860G families)

Many Casio graphing calculators use SHIFT + AC/ON for power off. Look for OFF above the AC/ON key area. If you are in an app or running a graph process, stop it first.

• Press EXIT until you are out of active operations.
• Then try SHIFT + AC/ON.

Basic calculators with no visible OFF command

Some basic models rely mostly on automatic shutdown. If there is no OFF printed anywhere and no dedicated OFF key, leave the unit idle and it should power down on its own.

Desktop/printing calculators

Many desktop calculators have a physical switch such as ON/OFF/PRINT or dedicated power key. Use that switch directly rather than SHIFT combinations.

If your Casio calculator will not turn off

1) Clear the current operation first

A very busy state (for example, an unfinished expression or running process) can make shutdown feel inconsistent. Press AC once or twice, then attempt OFF again.

2) Check for stuck keys

Dust, crumbs, or key wear can make SHIFT or AC fail intermittently. Press each key gently a few times. If one key feels sticky, clean around it with dry compressed air and a soft brush.

3) Replace weak batteries

Low batteries can cause odd behavior: dim display, slow response, random lockups, or failed key combinations. Fresh batteries often fix “won’t turn off” and “won’t respond” issues in one step.

4) Use reset only when necessary

If the screen is frozen, use the model’s reset method (button/hole/menu reset depending on device). Always remember this may clear memory, settings, or stored data.

Auto power-off behavior

Casio calculators are designed to conserve battery life. Many models enter auto power-off after several minutes of inactivity. The exact timeout varies by model and mode, but this is normal behavior and not a defect.

• Great for battery life when you forget to shut down manually.
• Useful during study sessions where you pause frequently.
• If your model has no manual OFF, auto-off is expected.

Examples for popular models

• fx-991EX / fx-991ES: SHIFT + AC (OFF).
• fx-570EX / fx-82MS: SHIFT + key labeled OFF (often AC).
• fx-9750GIII: Usually SHIFT + AC/ON (OFF function).

If your keyboard legend is worn off, look up the exact model PDF manual from Casio support and verify the key map.

Battery-saving habits that help

• Turn brightness down on graphing models when possible.
• Use manual OFF before storing the calculator in a bag.
• Remove batteries for long-term storage (especially over summer).
• Replace all batteries together; avoid mixing old and new cells.

FAQ

How do I turn a Casio back on?

Press ON, AC, or the model’s power key/switch. Graphing models typically use AC/ON.

Will turning off erase my calculations?

Usually no. Standard memory and settings are generally retained after normal power-off. A reset or dead battery can clear data.

What if there is no OFF printed anywhere?

Your model may rely on auto power-off. Leave it idle and it should sleep/shut down automatically.

Is it safe to press RESET every time?

No. Use RESET only for freezes or severe issues. Frequent resetting is unnecessary and can remove stored content.

Final takeaway

For most users, the answer to “how do you turn a Casio calculator off?” is simple: SHIFT + the key labeled OFF (usually AC/ON). If you cannot find OFF, rely on auto power-off or check your model’s manual. When the calculator is unresponsive, troubleshoot in this order: clear operation, try keys again, replace batteries, then reset if needed.