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Nathan, Engineer
Category: Consumer Electronics
Satisfied Customers: 24566
Experience:  Managing Director at Pollinate Group LLC
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How do I get back to regular calulations - the calulator says

Customer Question

How do I get back to regular calulations - the calulator says RPN?
Submitted: 1 year ago.
Category: Consumer Electronics
Expert:  Nathan replied 1 year ago.

Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.

Sorry to hear you’re having trouble.

RPN means reverse polish notation, a different type of entry syntax often preferred by engineers and physicists as it can be quicker.

Without knowing the model of your calculator, I can't give specifics.

If you look on the keypad though, not at the actual keys but above them, you should see a line that says RPN. Usually pressing the 2nd or Fn key + that RPN key will toggle it on/off.

For most HP models, you'd press the MODE button first, then the desired mode such as 4 for ALG (algebra), 5 for RPN, etc, following the outlines above your keys.

Best regards,


Customer: replied 1 year ago.
Your answer did not help or solve the problem. My calculator is the HP12c Platinum
Expert:  Nathan replied 1 year ago.

Thank you for the information.

I'm sorry it was not helpful initially, but as I mentioned without a model number it isn't possible to give a detailed answer.

Your calculator model is really intended for use with RPN format, it is most efficient that way.

You can change it over to ALG mode, but some functions don't work the same way.

To change, press F-key, RPN (over the CHS key) to toggle back.

Expert:  Nathan replied 1 year ago.

Do you need more help with this?