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Popular calculators

Rhombus - diagonals, area, perimeter, sides

Rhombus calculator will help you calculate the long diagonal of the rhombus, the short diagonal of the rhombus, the side length, height, area of the rhombus, radius of the circle inscribed in the rhombus.

Profitability of investments: NPV (Net Present Value), PI (Profitability Index), IRR (Internal Rate of Return), DPP (Discounted Payback Period)

This calculator helps us check whether the planned investment will be profitable and whether the project should be accepted or rejected.
Thanks to the calculator, we can calculate:
NPV (Net Present Value) - sum of discounted net cash flows
PI (Profitability Index) - investment profitability
IRR (Internal Rate of Return) - internal rate of return
DPP (Discounted Payback Period) - discounted payback period
Value of discounted net cash flow for each period.

Ventilation efficiency calculator in the bathroom, toilet or kitchen

With this calculator, we will find out what ventilation efficiency should have depending on the size, height and type of room, e.g. in the kitchen, bathroom or toilet. The ventilation calculator will help us choose the right fan for the selected room, e.g. it will facilitate the selection of the hood for the kitchen.

CAPM (capital asset pricing model) CML form - valuation of capital assets

The CAPM calculator can be used to calculate the cost of equity, to evaluate the investment effectiveness of collective investment funds (open-end investment funds, pension funds, etc.), to study the efficiency of the stock market, etc.
The CAPM model allows to illustrate the relationship between the incurred systematic risk, otherwise known as market or non-diversifiable risk, and the expected rate of return.

The CAPM calculator in the form of CML allows you to calculate the expected rate of return from the so-called the effective portfolio (on the border of Markowitz's effective portfolios).

Playing with the recognition of color shades - an eye test.

The calculator is used to test your eyesight and recognize the difference in color shades. After clicking on the first lighter field, the calculator will change colors and the countdown will begin. Each test takes 15 seconds. Search for a lighter field and click on it. Each subsequent test is more difficult. The test will be aborted if you do not give the correct answer within 15 seconds or if you make a wrong choice three times.

Force, mass and acceleration calculator

With this calculator you can calculate the force, mass and acceleration from Newton's Second Law of Motion.

Daltons law of partial pressures

Using the calculator you can calculate the partial pressure according to Daltons law.

Basal metabolic rate (BMR) - calculator

Using the calculator, you will calculate the basic metabolic rate (BMR-basal metabolic rate) and the amount of calories needed to supplement, i.e. burned by the body on an empty stomach (in the morning, without a meal), in physical and mental peace.

Ventilation in the attic/loft

The calculator is used to calculate the ventilation capacity in an attic or loft for the minimum, normal and extreme thermal conditions of the environment depending on the area and height of the room and the roof pitch. The fan removes warm air from the room and should be mounted at the highest possible point for the best efficiency.

Addition in columns

With this calculator you will learn how to add in columns. You can check if the addition you have made is correct

Smoking costs calculator

Calculate how much you spend smoking, so how much you could save after quitting smoking.

Bicycle tire pressure calculator

With this calculator, you will calculate the exact tire pressure required for your bicycle tires on the front and rear wheels depending on the load, wheel size, bicycle weight, etc.

Home heat loss calculator

This calculator is a complete tool to calculate the heat loss of your home Whit this calculator, we will find out what the heat losses are, e.g. through the ceiling, external walls, windows, floor in each room of our house, depending on the type of building material, number of layers, insulation and external temperature.

Child's blood group

You will calculate with fairly high accuracy the likelihood of your baby having a particular blood group.

Vernam cipher - encoder / decoder

Vernam cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Vernam cipher.

How to convert dog age to human age? Dog age calculator

How to convert a dog's age to human age? How old is a dog in human years? How long will my dog live? Dog Age Calculator will help you with these and many other questions.

Rail Fence, Zig-Zag - encoder / decoder

Rail Fence, Zig-Zag cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Rail Fence, Zig-Zag cipher.

Price, discount and discount rate of a treasury bill

This financial calculator will help you calculate the purchase or sale price of Treasury bills, the amount and the annual discount rate.

Percent concentration - volume

Using this calculator, you can calculate the volume percent concentration, also called the volume percentage of chemicals in mixtures and solutions.

Solving Systems with Gauss-Jordan Elimination calculator

You can calculate with explanations any system of linear equations, both homogeneous and heterogeneous with any number of unknowns by Gauss-Jordan elimination method. As a result, apart from the solution, you will also receive a complete analysis and a step-by-step calculation.



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