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Popular calculators

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 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.

Storm distance, lightning distance calculator. How far is the storm?

How far is the storm? How close is lightning? Is the storm looming or is it moving away? Surely everyone has asked themselves such questions. That is why we have created a lightning distance calculator with which you can easily check it.

Assessment of readiness to lose weight

Did you know that proper preparation is an essential factor in losing weight successfully? This test will not only help you answer the question of whether you have a chance of successful weight loss, but it will also indicate the factors that are necessary in preparation for this process.

Daily calorie calculator. So how much do we need a day to lose weight, gain weight or maintain weight.

The caloric demand calculator will help you create the right diet. It will answer the question of what is our daily calorie requirement and how much daily do we need to consume carbohydrates, proteins and fats to gain weight or lose weight by a given weight within a certain period of time.
We have a choice of several of the most popular formulas for calculating the basal metabolic rate. As a result, we will also get a seven-day alternating caloric cycle, thanks to which, with long-term diets, we can "cheat" the body by consuming different caloric values a day while maintaining a weekly diet.

Circle - geometric figure

Thanks to the calculator, you can easily calculate the area of a circle, the circumference of a circle, the area of a circle segment and the length of the circle arc.

Affine cipher - encoder / decoder

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

Linear Regression - calculator with explanation

With this statistical calculator, you will learn how to calculate a linear regression step by step.

Molar concentration

Using this calculator you can calculate the molar concentration of the solution, ie the number of moles of a given chemical substance that contains 1 liter of solution.

Ideal gas

Using the calculator, you can calculate the pressure, volume, temperature and volume of moles of ideal gas.

Vertical projectile motion - speed, time, height

With this calculator, you can calculate the velocity of a body thrown vertically after a specified time and the initial velocity given to the body. You will also calculate the time elapsed from the moment of the throw to reach a certain speed, the time the body flies to the return to the place of the throw and the time after which the body reaches its maximum height. The calculator will also help you calculate the height at which the body is located after a certain time and will calculate the maximum height that the body will reach. The calculator also allows you to estimate the gravitational acceleration which can be useful in determining where the body was thrown.

Fraction calculator - multiplying fractions step by step with explanation

With the Fractions Calculator, you can multiplying any two mixed numbers or proper and improper fractions.
Fractions Calculator will show you the result of operations on fractions step by step and will give you explanations of the operations performed to multiplying fraction. You will learn how to simplify fractions, how to find a common denominator, how to find the least common multiple and the greatest common divisor.

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.

Langevin function calculator

With the Langevin trigonometric function calculator you can calculate the values of the function. In addition to the response results, the calculator will also plot the selected function. You can choose a ready function, e.g. L(x) or enter your own function, e.g. L(x^2), L(x+3) etc.

Brick / block quantity calculator

The calculator is designed to calculate the amount of bricks or blocks needed. How many bricks do we need to build a wall of the given size, including wall openings and joints, how many bricks should we order, taking into account waste and what will be their weight.

Calculator for maximum heart rate and heart rate zones for training

How to calculate your Maximum Heart Rate (HRMAX)? Which heart rate zones to choose for training and how to calculate the heart rate zones? At what heart rate is the best fat burning, and at what will we increase our efficiency and improve the condition? The calculator for maximum heart rate and heart rate zones can help answer these questions. You will calculate both your maximum and optimal heart rate and select the heart rate ranges for the appropriate training.

Matrix 2x2 calculator

Thanks to the mathematical calculator, you can easily calculate the determinant of the matrix, find the complement matrix, the transposed matrix, and the inverse matrix.

Heart attack risk

Thanks to the calculator, you can use several factors to check the degree of risk of a heart attack in the next ten years.

Brinell hardness scale

With this calculator you can calculate the HB hardness or the hardness of metals based on the Brinell hardness test.

Arithmetic sequence calculator

You can easily and quickly calculate the sum of an arithmetic sequence, calculate the value and the difference of an arithmetic sequence or find the nth expression.



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