Last updated: August 6, 2021

You want to be sure that certain things have been calculated correctly? Then you should think about buying a calculator. With the help of a calculator, you can not only be sure that the result is correct, but also that it can be calculated much faster. In addition, you will not be able to solve certain complex calculations without a calculator.

Which calculators are suitable for you? What are the different types of calculators you can buy?

You can find answers to the most frequently asked questions here in the big calculator test 2021. We present various calculators to help you decide which one to buy. In addition, you will find helpful tips and tricks in our guide on when to use deg and rad with your calculator. No matter which type of calculator you finally decide on, we will tell you about the advantages and disadvantages of the different types.



  • A calculator is a useful gadget and not only for school or an accountant, but also for quickly calculating your own finances and purchase prices.
  • When buying, you can choose from simple calculators, desk calculators, financial calculators, scientific calculators, graphing calculators and CAS calculators.
  • A calculator is powered either by battery, solar cells or dual power. Some models are even equipped with a memory on which important intermediate results can be stored.

The Best Calculator: Our Choices

Guide: Questions you should ask yourself before buying a calculator

What are the advantages of a calculator?

Maths problems and calculations can of course also be done without a calculator. For example, you can use mental arithmetic or written methods. However, you will soon realise that problems can arise. Therefore, the following advantages can be summarised when using a calculator compared to other methods:

  • Calculating tasks is significantly faster
  • Fewer mistakes are made
  • Some tasks can only be solved with a calculator

Many of the tasks can be solved in writing or in the head, but often require several steps, which takes a lot of time compared to the calculator. Performing these steps also involves a potential for error, which is massively reduced when using a calculator. In addition, the methods mentioned can still be used well for simple tasks with small numbers, but are more difficult or impossible to use for more complex types of tasks.

A calculator is indispensable for calculating difficult and complex maths problems quickly and reliably. (Image source: / Myriams photos)

Calculators are therefore the only option if you want to calculate complex and difficult maths problems quickly and safely. This will help you to master even the most difficult tasks.

Which calculators are approved for me?

Important: If you are not going to use your calculator for school/university, you can skip this section. Apart from the private use of a calculator in everyday life, the calculator is most commonly used by students at school and university. Unfortunately, not all types of calculators are allowed at school and university. Therefore, we would like to briefly explain where which types of calculators are permitted.

For a better overview, we have created a table with all the federal states and the approval of the calculators, this table is only valid for the schools in the federal states:

In general it can be said that programmable calculators are almost never allowed and GTRs are often not allowed. To be on the safe side, you should therefore check your examination regulations or ask your lecturer directly, as this is the only way to avoid making a mistake.

Which calculators are suitable for me?

It all depends on what you want to do with the calculator. In general, the more complicated the tasks you want to calculate with the calculator, the more functions it should have. Thus, the area in which you want to use the calculator is a very important factor in your decision.

First of all, you should be clear about the area in which you want to use the calculator. For simple and everyday calculation tasks, a simple calculator is recommended, as the basic functions are completely sufficient for you. However, as soon as you want to calculate tasks that go beyond everyday use, you should choose a different type of calculator.

As soon as you want to use the calculator at school, you should clearly switch to one with more functions. We recommend a CAS calculator. The advantage of being able to solve algebraic calculations in addition to graphing is a decisive advantage for us. In particular, solving algebraic calculations gives you a big advantage in the exam and can make the difference between two grades.

However, don't forget to check in our table beforehand whether such a calculator is allowed in your federal state.

Unfortunately, the situation is different at university. There, as already mentioned, it depends very much on your lecturer which calculator you are allowed to use. But here, too, we advise you to take the calculator that has the most functions. Because here, too, one more function could make the difference for a better grade in the exam.

Here we divide professional life into three sub-areas.

The first area relates to general professional life, the second area to commercial professions and office professions in general, and the third area specifically to the financial sector. In general, as mentioned above, the more complex the maths tasks, the more functions the calculator should have. But in most cases, a scientific calculator is more than sufficient in terms of its range of functions. Graphing calculators or even CAS calculators simply do not provide enough added value to justify a purchase.

If you have an office job or a commercial job in general, you should consider a desk calculator. Desktop calculators have the great advantage that their design and functions are specifically designed for commercial professions. For example, the large keys and simple design make input easier. While functions for calculating taxes, for example, can speed up work in the office immensely.

The financial sector is an exception. If you work in this sector, you should think about buying a financial calculator. Financial calculators have the advantage that they can calculate financial mathematical tasks (internal rate of return, annuities, etc.) in addition to the basic arithmetic operations. This makes financial calculators a handy and portable alternative to the usual spreadsheets used in these professions.

Battery, solar or dual power? - Which energy source is best?

For a calculator to function properly, it naturally needs some kind of power supply. A calculator can have one of three possible types of power supply. The three possible types of power supply are:

  • Battery
  • Solar
  • Dual Power

It can be said that calculators that are battery-operated only have a lower purchase price. Dual power calculators are more expensive, but the battery consumption is slower with this type of power supply. This has the advantage that you don't have to deal with annoying battery changes as quickly and you also save money in the long run because you don't have to buy as many new batteries.

With solar power, you have the advantage that you don't have to change batteries at all, and calculators with solar cells are also better for the environment. One disadvantage of solar calculators is that they depend on sufficient light. If this is not guaranteed, the calculator will not work. You also have to remember that only very simple calculators with few functions can be powered by solar energy.

In general, you should definitely choose Dual Power if you plan to use your calculator for a longer period of time. Due to the saved batteries, you will quickly recoup the higher price. However, if you are planning to buy a rather simple calculator anyway, a solar calculator is a good option because of its environmental friendliness.

People often think that a calculator with dual power draws its energy exclusively from the solar cell. Unfortunately, this is a common misconception. The solar cell does contribute to the power supply of the calculator, but most of the energy is still supplied by the battery. Therefore, you will unfortunately not be able to avoid changing the battery completely.

How much does a calculator cost?

The price of a calculator depends on the number of functions it has. Generally speaking, the more functions a calculator has, the more expensive it is. Therefore, the simple calculators are the cheapest and the CAS calculators are usually the most expensive.

For example, the price of a calculator can range from €6.90 for the simple Genie 840 S calculator to €152.89 for the CAS CASIO Classpad II calculator. It is important that you know exactly how many functions you want in your calculator.

The following table shows how prices vary depending on the type of calculator:

Calculator type Price range
Simple calculators 5 - 15 €
Desktop calculators 10 - 20 €
Financial calculators 25 - 70 €
Scientific calculators 40 - 100 €
Graphing calculators 100 - 200 €
CAS calculators 150 - 220 €

Decision: What types of calculators are there and which is the right one for you?

Generally speaking, you can distinguish between six types of calculators:

  • Simple calculators
  • Desktop calculator
  • Financial calculator
  • Scientific calculators
  • Graphing calculators
  • CAS calculator

These calculators differ mainly in the number of functions and thus in the possible range of use for the calculator. The individual advantages and disadvantages of the respective calculator result from the range of use. Therefore, the price and the area for which you want to use the calculator play important roles in choosing the right calculator for you.

To make your decision as easy as possible, our guide introduces you to the types of calculators mentioned and goes into more detail about their advantages and disadvantages.

Simple calculator - What are the advantages and disadvantages?

Simple calculators are the simplest and most basic calculators you can buy. They only have the basic arithmetic operations and the percentage calculation. Because of the small number of functions, the price of the calculator is also very low compared to the others. So if you don't have any special requirements for your calculator and only want to do basic calculations, then a simple calculator is the best choice for you.

  • Very low price
  • Suitable for everyday and simple calculations
  • Hardly any other functions
  • Too simple for use at school and university

Desktop calculators - What are the advantages and disadvantages?

Desktop calculators are mostly used in offices or similar commercial professions. Desk calculators are very similar to simple calculators. However, in addition to the functions of the simple calculator, they also have functions such as currency conversion and various tax calculations.

The design of the calculator is designed to be optimally suited to office work. Large keys and a large LCS display, for example, are designed to facilitate input and overview. There are even desk calculators that allow you to print out the typed results directly on a paper roll attached to the calculator.

  • Ideal for office work
  • Low price
  • Simple and clear design
  • Few functions
  • Too simple for use other than in the office

Financial calculator - What are the advantages and disadvantages?

Another calculator designed for professional use is the financial calculator. A financial calculator has the advantage that it has extra functions for calculating financial tasks in addition to the functions of the simple calculator. For example, it is equipped with functions such as calculating the internal rate of return or the present value.

Apart from these special functions for the financial sector, however, the financial calculator has no other functions or extras. Therefore, a financial calculator is the best option for you if you work in the financial sector or are a student graduating in the field of finance.

  • Specially designed for working with finances
  • Compact and simple design
  • Medium price
  • No graphing
  • Outside of finance, the extra features are less useful

Scientific calculator - What are the advantages and disadvantages?

In addition to the basic arithmetic operations, scientific calculators can also perform scientific functions such as the angle function and logarithm. It is also possible to recall and edit past calculations.

The possibility of calculating scientific functions extends the range of use of the scientific calculator beyond everyday life. Therefore, the scientific calculator is particularly interesting for you if you need a calculator for university or school.

  • Scientific functions (angle function, logarithm, etc.)
  • Suitable for university and school
  • Almost all models are approved by university and school
  • Cheaper than graphing calculators
  • No graphing possible
  • Not programmable
  • Already too complex for everyday calculations

Graphing calculators - What are the advantages and disadvantages?

In addition to the functions that the scientific calculator already has, the graphing calculator can also display simple graphics (function graphs and diagrams). Many of the graphing calculators are also programmable, which allows you to install your own calculation programs and even games on the calculator.

The graphic calculator is an interesting alternative to the scientific calculator because it can display simple graphics. The graphical representation of certain mathematical tasks can often help to understand them better. It should be noted that many graphing calculators are not allowed to be used at university.

Therefore, if you want to use the calculator at university, you should consider another type of calculator. If you want to have a calculator for school that is able to display simple graphics in addition to the scientific functions and you are willing to accept the higher price, then the GTR calculator is a sensible alternative for you.

  • Graphical representation (function graphs and diagrams)
  • Mostly programmable
  • Scientific functions
  • Suitable for school
  • Not allowed in most universities
  • Significantly more expensive than a scientific calculator

CAS calculators - What are the advantages and disadvantages?

In terms of the number of functions and the size of the area of use, CAS calculators represent the crème de la crème of calculators. In addition to the functions of the GTR calculators, CAS calculators can also solve algebraic tasks (systems of equations, matrices, etc.) completely by themselves.

CAS calculators are one step above GTR calculators in terms of their range of functions. The function of solving algebraic tasks yourself makes it much easier for you to calculate certain algebraic tasks. Unfortunately, this calculator, like the GTR calculator, has the problem that it is not approved for most universities.

However, if you want to use it at school, it has the advantage that it is not permitted in only two federal states. So if you want a calculator that, in addition to the functions of the other calculators, also gives you the option of solving algebraic problems and you are happy to pay the higher price for it, then a CAS calculator is the right choice for you.

  • All the functions of the other calculators
  • solving algebraic tasks possible
  • approved for school almost everywhere
  • Not allowed in most universities
  • Most expensive compared to the other alternatives

Buying criteria: Use these factors to compare and evaluate calculators

Next, we would like to show you several criteria that will help you compare calculators better. With these, it will be much easier for you to find the right calculator for yourself. In summary, these factors can be used for this purpose:

  • Type of calculator
  • Power supply
  • Characters per line
  • Programmable
  • Functions
  • Equations
  • Scientific functions
  • Memory

In the following paragraphs, we will explain these factors in more detail and highlight which characteristics are desirable.

Type of calculator

The different types of calculators have already been discussed in more detail above. Nevertheless, we would like to emphasise that the type of calculator is one of the most important decision-making criteria. To choose the right type of calculator, you should be sure what you want to use it for.

As a general rule, the more complex the calculation tasks, the more functions and extras the calculator should have. However, you should not forget that there are also specialised calculators, such as the desk calculator and the financial calculator.

So you should not disregard specialised calculators just because they have fewer functions than comparable calculators.

However, we will not go into any more detail in this paragraph, as we have already done so in two paragraphs above. If you are still not sure about this criterion, you should read

Decision: "What types of calculators are there and which one is right for you?" and "Which calculators are right for me?"

Power supply

This criterion indicates from which source the calculator gets its power. The possible energy sources for a calculator are divided into battery, solar and dual power. The type of power supply mainly influences how often you have to change the batteries of your calculator or, in the case of solar power, whether you have to change them at all. In general, it can be said that dual power is superior to battery power.

Apart from that, however, it is difficult to give a general recommendation, as it depends on what you personally value more. That's why we recommend you read the paragraph "Battery, solar or dual power? -Which energy source is best? " in case you don't remember the advantages and disadvantages of the different energy sources.

This will help you to make the best possible decision

Characters per line

This value indicates how many characters fit on one line of the display. On simple calculators and most desktop calculators, this number also limits how long the calculations you can enter into the calculator are. This limitation is not present in all more complex calculators, as it is possible to select numbers that are not currently visible on the display with the cursor keys.

The standard number for this factor is usually 12. The more characters a calculator has per line, the better this is to be rated. Even if more complex calculators are not limited by this number in the range of the calculation length, it is simply clearer to see the entire calculation directly on the display.

Therefore, if you calculate with many decimal places or complex calculations, you should not neglect the characters per line as a decision criterion. This is especially helpful if, for example, you have made a mistake when entering the calculation and you can find the error more easily because of the better clarity.

It should also be mentioned that the different types of calculators have different numbers of lines per display. While scientific calculators usually have two lines per display, graphic calculators usually have five to six lines per display.


If a calculator is programmable, this gives you the option of using your own programmes to calculate tasks in the calculator. It is also only possible to install and play games on a programmable calculator.

As soon as a calculator is programmable, this opens up completely new possibilities for using the calculator and makes it significantly more useful. Therefore, it is almost always a positive thing when a calculator is programmable.

The only exception is at university, where almost all universities do not allow programmable calculators to be used in exams. All CAS calculators are programmable, as are a large proportion of graphing calculators. This is not normally the case with all other types of calculators, but it can happen if necessary. Therefore, it is important that you check this separately before buying the calculator.


The factor "functions" represents all possibilities of the calculator to calculate tasks that use more than just the basic arithmetic operations for their solution. This extends from various functions of financial mathematics (e.g. internal rate of return) to scientific functions (e.g. trigonometry).

Thus, this factor is present in all pocket calculators except the simple pocket calculators. The more functions a calculator has, the better it is for the rating. This is because functions increase the scope of use of a calculator.

However, you should also keep in mind what exactly you want to calculate with the calculator. For example, a financial calculator has fewer functions, but its functions are specifically designed for the financial sector.


This criterion describes the ability of the calculator to solve equations by itself. Generally speaking, graphing calculators and CAS calculators are always able to solve equations. This is not always the case with scientific calculators and should therefore be checked again.

Similar to the criterion "functions", the presence of this function in a calculator is an advantage and should therefore flow positively into your evaluation. By automatically solving equations with the calculator, you can often save a lot of time and also minimise your error potential.

It should also be noted that there are differences in the type of equations the calculator can solve. As a general rule of thumb, it can be said that scientific calculators can only solve simpler equations, such as systems of linear equations. Whereas CAS calculators are able to solve significantly more complex equations by themselves.

Scientific functions

While the factor "functions" was rather general, "scientific functions" refers specifically to whether the calculator is able to calculate scientific functions (e.g. angle function and logarithm). Calculating scientific functions is supported by all WTR, GTR and CAS calculators and is a plus point in the evaluation because of the greater benefit it offers you.

Without these functions, you would otherwise have no way of calculating certain tasks with the calculator in the first place. In the final years of school and especially at university, calculators that have scientific functions are therefore a must.


The memory space indicates how many variables the calculator can store at once. In CAS calculators, the memory can also be represented in the form of kilobytes or megabytes. In addition to the number of variables, the memory space also indicates how much space the calculator has for its own programmes.

The more variables or the more kilobytes/megabytes the calculator has, the better it is. Storing variables gives you the option of inserting variables that you use often directly into the calculation by pressing a key.

This can save you a lot of time, which is very important in exams, for example. It should also be mentioned that the memory capacity of programmable calculators also limits how many games you can install and play on them.

Facts worth knowing about calculators

When did the first calculator exist and what did it look like?

Even before the first electronic calculator was introduced, there were similar alternatives, such as slide rules or mechanical calculators. However, these were not handy and not as practical as the calculators we know today.

Did you know that the first palm-sized calculator was developed in 1967?

It was made by Texas Instruments and weighed 1.5 kg. In contrast to other earlier devices, the "Cal Tech" already ran on batteries instead of a power connection.

Can I play games on my calculator?

Although it is not possible with all calculators, it is possible to play games on a calculator. For this to work, you need to make sure of several things beforehand. First of all, you must have a programmable calculator, on all other calculators it is not possible to install games or similar.

The calculators that are programmable are usually the GTR and CAS calculators. It is also only possible to play very simple games, such as Tetris, on your calculator. Once you've figured these things out, you can look for a tutorial on the internet and try it out yourself.

When do I use deg or rad on my calculator?

Scientific, graphing and CAS calculators have the option to switch between "deg" or "rad". Below we briefly explain what these functions mean and when it is best to use them. Deg is the default setting on most calculators. In this setting, the degrees for a right angle are 90° and for a full circle 360°. You will use this setting most of the time, for example, when you want to calculate the sums of the angles of a triangle.

Wheel uses radians instead of degrees. You should use this setting when calculating with Sin, Cos and Tan. In all other cases you should leave the setting at "Deg". It is important that after you have used "Rad", you set your calculator back to "Deg". Otherwise, your calculations may produce incorrect results.

Are there calculators that only run on solar energy?

Most calculators nowadays are equipped with a solar cell, which leads to the question of whether they draw all their energy from the solar cell. Although the calculator draws part of its energy from the solar cell, this amount of energy is by no means sufficient to supply the calculator completely with energy, especially in the case of more complex calculators (GTR, CAS and WTR).

For more complex calculators to work only with solar energy, the solar cell would have to be about as large as the calculator itself. Therefore, it is only possible to operate a simple calculator with only a few functions using solar energy.

Are there calculators that have a camera or wi-fi?

Since the introduction of the first pocket calculator, the calculator has constantly evolved and gained more and more extras. Although there are already calculators with colour display and touch screen (CASIO Classpad II), there are still no calculators that have a camera or wi-fi. It also remains to be seen whether this will ever happen, as the advantages that would be gained from it will probably not be great enough.

Image source: / Charles Deluvio

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