What's the most reliable, best built HP Calc in the last 25 years?


I was wondering what the best built, most reliable HP calculator has been over the last 25 years? Looking to add a backup and wanted to get the best. Any HP calculator will suit my needs, as long as it has RPN. Expandibility and memory are not a concern. Number one priority is getting something that will last a long long time.


A voyager. 10/11/12/15/16C

Although the newer 12C's must be excluded from the list.


Agreed. Almost all of the old LED models were quite reliable. However, they all used rechargeable batteries,
and some have suffered outgassing and subsequent corrosion
damage after all these years. Additionally, these calculators contain a relatively high number of discrete
components. Some of the components, such as capacitors, start going bad after a while.

The Pioneer series (HP-32SII, HP-42S, and others) do not have such problems, although their keyboard construction is not as robust as on earlier models.

Definitely the Voyagers.

Larry M.


Interesting to notice almost a role reversal between HP and TI. HP made expensive and reliable calculators, while TI made inexpensive calculators that don't seem to be working today.

Today TI makes calculators that are more robust and powerful .... AND owns the market. HP has taken second place.

Oh well .... life IS strange!



You forgot the Casios and other Kinpos ;-)




Right you are! I have a Casio ClassPad and it kicks butts!!



TI has never made anything that is anywhere near as nice as an HP. It is mostly junk-like. I'm not speaking of functionality.


Hello Mike,

If nobody responds to your TI "Junk" comment - I have to...

I received yesterday from TI the 2004 model of the TI-89 for my www.datamath.org museum. Please believe - it is a real cutie !
The colour of the housing is now dark blue instead the black plastics and the display bezel changed to silvertrim. The whole calculator is a reminiscence of the wonderful SR-50. You remember the SR-50 ? It was TI's answer to the HP-35 and IMHO the best engineered TI calculator ever (but still a half class behind the HP-35).

Don't miss the new TI-89...



Mayby you should not be as concerned with basic reliability, but with long term maintainability. Although the Voyager series are very reliable, they tend not to be very repairable if they ever do break.

I would probably choose the HP67. It is a very reliable machine to start with (once you replace the card reader drive roller). It shares many components with other woodstock series machines. Pick up an extra charger or two along the way. The connection in the plug tends to break.


No question. Best regards from V.


There may be 12c calculators still working 200 years from now (in spite of Valentin's points about degradation!).


I say the HP-71B is the best of the handhelds, calc or computer. It is one powerful device. And very well made.

But of the calculators, the HP-15C is my favorite for a pure calculator and nothing else. Compact, nicely designed and powerful.

Edited: 1 Nov 2003, 8:07 p.m.


So, it sounds like a majority of the people who responded think that the 10c-16c series of calculators is the safest bet for having a reliable calculator well into the future? More reliable than the 32s, 32sii or 42s calculators? How about the 41 series? The 41's seem to have had trouble with the battery's. Too bad.


John posted:

"So, it sounds like a majority of the people who responded think that the 10c-16c series of calculators is the safest bet for having a reliable calculator well into the

Definitely. But they *must* be USA-made models, for maximum reliability and better durability. Ones made in other countries (such as Brazil) aren't as sturdy or well-built, many of them having the key letterings painted over molded keys of other models, and thus prone to erasure given enough time and use, let alone China-made HP-12C's which are abysmal quality, specially the keyboard.

"More reliable than the 32s, 32sii or 42s calculators?"

Certainly. Specially the 42S's display, which being a dot-matrix type has a lot more elements (pixels) than the simpler, segmented LCD display of Voyager series, so it's more prone to eventual failures in the future.

"How about the 41 series?

Wonderful as they are from a functional point of view, they don't come even close in sturdiness and long-term reliability when compared to Voyagers.

Just to further emphasize my point, I've got some 12 or 14 Voyagers when I last counted, and you'd be well advised to get some as well, high prices notwithstanding. Else, you'll have to kiss RPN goodbye far earlier than me. You've been warned ... :-)

Best regards from V.


Valentin wrote, in answer to the question in italic :

"So, it sounds like a majority of the people who responded think that the 10c-16c series of calculators is the safest bet for having a reliable calculator well into the future?

Definitely. But they *must* be USA-made models, for maximum reliability and better durability.

I'm no engineer but I had the impression that the Singapore made calculators, especially the 41 and pioneer series, were as solid as the US made... Am I wrong ?


I'm no engineer but I had the impression that the Singapore made calculators, especially the 41 and pioneer series, were as solid as the US made... Am I wrong ?

No, not at all. In general, that is my opinion as well but it should be qualified. You where correct when mentioning the 41 and Pioneers as having been made in Singapore. I have never seen an 11C or 15C made in Singapore as those models were being discontinued as early Pioneer production shifted from the USA to Singapore. So, AFAIK, the 12C was the only Voyager made there. I see no difference in construction or quality with USA or Singapore 12C's. The same is true of the 41's and Pioneers. When the Pioneers moved to Malaysia - this marked the beginning of the decline in quality with the first appearance of painted keys. The Malaysian 12C's were only marginally better than today's Chinese paperweights, which is not a compliment.

I have repaired several Brazilian 11C's and see no difference in quality vrs USA models with the exception of the rubber feet being made of a thicker, different material.


I agree that the brazilian Voyagers are very good indeed, regardless that I'm brazilian. I had a HP-15C build in 1983 here in Brazil that is identical of the USA version. My atcual 15C is brazilian also, as my 11C.
The most recent ones doesn't have the extra rubber protective layer around the circuit board, but they are very good.
The Pioneers are identical also, I have a 42S and a 32S made in Brazil that are the very same as others I saw made in Singapore or USA.
Their components are all USA and Japan made and the keyboard legends are molded, not painted.




Yes, forget about the 12C, that was built at several places.

I also never saw any voyager made outside the US.

But' I've got in my collection several "S" and "A" 41 C, CV and CX and I can't see a difference between them.

The same applies to 42S, 17BII, 32S and early 32SII, as weel as spice series : I've got in my hand 2 38C, 1 "S" and 1 "A" and I reaaly couldn't tell which one is betterly made...

BTW I have 2 "ID" 19BII and the qality seems pretty much alike my "S" 19BII.

I think that the quality difference was noticeable in the mid 90s production, where it was shifted to Malaysia and China...

Just a feeling, no certitude of course !


I have an American made 42S and I put it on a while back, nothing came on. I checked the voltage and it was a little over 2 volts. I changed the batteries, knowing I got to type back all these programs. When it powered up, to my amazement all programs were intact. This never happened to any of my other 42S, including 3 Singapore and 2 Indonesia made ones.
Additionally you never hear any clicks when the buttons are pressed. Something all to common with the ID made ones.


I do think the HP-25 was one amazingly solid calculator. The main damage being from battery leakage and using without good battery connection. 25C's were electronically more fragile as well.

Otherwise, this baby can be blown through a snowblower, run over by cars, buried in snow, and many other horror stories I've read about... I always liked how it could be used as a football (something I HAVE done with a well-abused spare). I think the secret is the uni-body case and modular design which leaves no room for disconnection once assembled. I'll bet it can be physically abused more than any other model series.

And my spare 71b has survived many a fall unharmed (as I've fallen asleep playing games in the ... library...)

I can't disagree, however, that the Voyagers are the most surviving calculator overall. I just wouldn't want to try the above "tests" with one <grin>.



Although the HP25 is one of my favorite machines (it got me an EE degreeee) it is probably the least reliable HP machine becuase of it's infamous power supply problems. It is electrically much more fragile than the HP21... the ACT chip and/or the RAM chip just love to die. My estimate that if you were given a box of a random selection 100 HP25 machines, over 50 would be bad. The same selection of HP21 machines would have 15-20 bad machines.


The Voyager Series (10C to 16C), definitely. Of course, you have to exclude the "12C" built in Malaysia, China, and this strange Platinum version.


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