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Calculators

HP 48 series

5owners with an opinion
60%of verdicts positive
1/1positive/negative since 2024
0happy after 3+ years

Praised for ease of use and display; criticized for performance.

What people wrote

Doesn’t like it
Today, the thing that makes the HP48 series much less useful is simply that they lack a backlight. I find them simply difficult to read and use today because of that. So, I just use a HP48 app on my phone. It's not as good, lacking the tactile response of the keyboard. But it's close. I used to program the 48's. You think laptops are convenient, wait until you try coding in bed on a 48. Very comfortable, if you can stay awake :).
Doesn’t like it
> I also have a HP-48SX, but it sees much less use – the buttons are not nearly as pleasant and the screen is harder to read. I have an 11C and both a 48SX and GX. I don't really think the keys on any of those were close to being in the same league as my Dad's old HP-38C. https://www.hpmuseum.org/hp38.htm Agreed on the display, but HP got it better on the GX. In retrospect, all of the 48/49 series calculators struggled with their UX... The UI was complicated by their attempt to be a general purpose calculating tool, but the hardware wasn't up to the ambition and computers/laptops ate their lunch in professional settings.
Likes it
I've tried Free42, but never really warmed to it. More comfortable on the 48/49/50. That's pretty much delegated to an iOS app now, but mostly because of the backlight. The display is simply better. The keyboard not so much (being a touch screen), but win some, lose some. I certainly like the programming model of the 48 series over the 42. RPL is a really delightful language and environment to work with on device. I never did much off device work, but coded up a bunch of stuff back in the day on the calculator itself. REPL development doesn't get much purer than this. Along with a stepping facility, and trivial unit testing, it makes developing stuff a real treat. I can honestly say there's nothing easier to work on when lying in bed.
Likes it
HP48 was awesome, but now, quarter century later, I like HP42 (also Saturn-based) better. It’s more convenient for simple tasks, and I no longer need to do complicated ones on a calculator. It’s also way faster, and smaller - it’s exactly the size of my iPhone; HP48 is about 50% longer and much thicker. Also, iOS version of Free42 is epic.
Likes it
The HP48 series does exceptionally for basic scientific and engineering computation against computers with modern languages like Python. I could compute, script, and similar in it very efficiently. The problem is: 1) It's an integrated implementation. For example, RPL makes sense when you have the brilliant HP48 keyboard, and one-key access to many of the commands. It makes little sense if you're manually typing things. The number of keystrokes would go up 3-4 fold on a PC keyboard, and correspondingly, the number of stupid errors. You can't mistype a command if it's one button, or two keystrokes through the menu system. 2) Getting all of that integration, synergy, and polish requires a huge engineering and design effort and brilliant people. One-off projects can't meet it. A lot have tried. 3) The newest HP48 has a 4MHz 4-bit CPU, 128kb of user RAM, and a 131x64 pixel display. This isn't competitive in 2022. I'd love to have a modern HP48, with an 800MHz CPU, gigabytes of RAM, and a high-res display, but to be at all worthwhile, it'd need to have the same quality keyboard, the same level of polish, the same community, and otherwise. I don't think that's gonna happen. Unfortunately, HP calculators peaked with the 48GX. Newer models were faster but gradually lost the polish of the older models.