What’s New

Version 4.6.5

Updated all scientific constants to the latest CODATA 2018 values, and now include the full list.
Improved accuracy of stored numbers when PCalc isn't running, and for copying and pasting.
Improved the UI for using multiple memories in the widget.
No longer show the "M" indicator when other memories have contents, but "Use Multiple Memories" is off.
Added new line display types that show a running total for the current calculation, the "Last X" value, and all the memories.
Added an option for displaying all function variables in the registers section.
Fixed a problem with still being able to click buttons that weren't enabled.
Titlebar buttons now work with VoiceOver and AppleScript.
Polyhedral dice!

Ratings and Reviews

4.7 out of 5
60 Ratings

60 Ratings

IanJ78 ,

PCalc 4.5.3 on 10.8 bug

This is really a great app, but I'm using 10.8.5 Mountain Lion, yes I know it's an old os, and there's a bug I noticed.
About a third of the time opening the app, the number screen comes up blank. Not with a zero or anything else, just blank.
After a few more times of closing then opening, it works fine again, finally showing numbers. Is this just a Mountain Lion bug,
or is anyone else having this problem? Oh well, it actually works sometime, just wondered if anyone else has experienced this too.
I'm using version 4.5.3.

beast006 ,


If you’re an engineer, programmer, scientist, number lover, or calculator fanatic then welcome home. This app is for you. You will be giddy with happiness from the functionality and ui. You will experience joy you never thought a calculator could possibly bring you. It can even calculate the ultimate number.

-To the devs, thank you so much. I’m estatic that I found this app. It’s like my years of frustrated search has concluded. A search I didn’t realize existed until I found this. I never have to switch calculators or get frustrated from limits.

campyguy ,

Not the "best" calculator - PCalc is the "perfect" calculator

My engineering days are pretty much over since I started up a new business, now that I am running my own business I'm using PCalc even more than before on my Mac and on my iPhone. The depth of this app's capabilities still surprises me.

So happy with the HP48 RPN mode! I still own one to go with my HP15 from the late 80s... Yep, I'm old.

Never a upcharge for upgrades, I just forked over on the iOS app with a large tip (for additional app colors, completely unnecessary purchase) to keep TLA's lights on...


TLA Systems Ltd.
29.9 MB

OS X 10.8 or later, 64-bit processor



Age Rating
Rated 4+
© 1992 - 2019 James Thomson


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