HP 20s Business/Scientific Calculator

The HP-20s is a great calculator. It features easy-to-use algebraic entry and a built-in program library of over 100 built-in scientific and mathematical functions. This powerful built-in program library eliminates the need to input frequently-used functions such as root finder, Simpson’s Rule of integration, complex number operations, 3x3 matrix operations, quadratic formula, and curve fitting programs. When using the HP-20s, these features are available at the touch of a key.

Essential trig and math functions for scientific applications are of course available. Sine, cosine and tangent, or exponential, natural log and antilog functions are only a few of the functions that can be used with the 20s.

The HP-20s performs English / metric conversions and fast conversions for mass, distance, volume and temperature.

Introduced in 1989, this calculator belongs to the last rock solid series of calculators produced by Hewlett-Packard at the end of 90's. You can place it in the pocket of your shirt and forget about it. Thin, light and efficient, you will appreciate its black stylish dress! HP made its name on calculators and this model is one of those that reminds us why!!!

The HP-20S has been produced first in USA and Singapor (we can identify it because it shows 5 rubber feet on the back) and secondly in Indonesia (this one shows 3 rubber feet only on the back). The american and singaporian models are the one to look for, particularly if you are a collector (USA one is the best). Keep an Indonesian model if you like variations.

The HP 20S is an excellent Calculator. It is a do-it all scientific calculator, and despite being Algebraic Entry is very useful and compact. The button feel and accuracy are very attractive features of this calculator.

*Self test by Pressing the [C] key and [y^x]. Press any key and begin the keyboard test left to right and top to bottom.

*Reset by pressing [C] and [LN].

If you're looking for RPN, buy the HP32sii- they look very similar, but inside they are not. The 32sii costs twice as much, but is worth it.

Related Calculators:
The 20S is a part of the Pioneer Series of HP calculators made from 1989 until 2000 or 2001. The Pioneer 10-series contained the Business Calculators: the HP 10b, 14b, 17b, 17bii. The Pioneer 20-series contained the scientific (algebraic) calculators including the 20S, 21S (Statistics), 22S and 27S. Lastly, the Pioneer 30 and 40 series contained the high-end RPN scientific series: 32S, 32sii, and the 42S.

Great calculator - same quality as the RPN HP calculators, but easier to use for non scientific people as it features = button. Also made in USA.

I bought this calculator after buying the 35s. Although the HP 20s is much simpler to use and has a really good tactile feel to the keys it lacks the publication data that the 35s so richly enjoys. Enough said about that the calc is layed out well and does enough programming to keep anyone busy for a weekend, I am still ready to buy more of the rpn calculators to try out.

This is a very sturdy and well mad calculator. The keys are crisp and solid. The markings are very easy to read. I have only just begun using it. I used to have a 48GX and am preferential to the RPN style input. This uses algebraic. It's a fine inexpensive calculator. I have not used any of the programming functions.