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Popular calculators

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.

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.

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.

Caesar cipher - encoder / decoder

Caesar cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Caesar cipher. You can use any shift and additionally a key for more precise text encoding.

Pentagon - diagonals, area, perimeter, sides

Pentagon calculator will help you calculate the long diagonal of the pentagon, the medium diagonal of the pentagon, the shorter diagonal of the pentagon, the side length, height, area of the pentagon, circumference and radius of the circumscribed circle and the radius of the circle inscribed in the regular pentagon.

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.

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.

Am I going bald? When will I go bald?

Are your hair falling out, are you starting to go bald? Use this calculator and check the probability and age at which you may be at risk of total hair loss.

Density, mass, volume

With this calculator you can calculate the density of the substance, i.e. specific mass. The calculator will also help to determine the mass of the substance and the volume it occupies.

Bacon cipher - encoder / decoder

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

Body fat content - a method of measuring skin folds in 3 places

The Body Fat percentage calculator will help you calculate the amount of fat stored in your body. It uses a method of measuring skin folds in three different places on the body.

Trifid cipher - encoder / decoder

Trifid cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Trifid cipher. You can use any shift and additionally a key for more precise text encoding.

Kinetic energy calculator

With this calculator you can quickly calculate the kinetic energy of an object. You will also calculate mass from energy and velocity and speed given kinetic energy and mass.

Daily calories burned calculator

Thanks to the calculator, you can easily calculate the amount of calories you burn every day. There are over 600 different activities available, from which you can choose those that were or will be performed on a given day and set the duration for each selected activity.

As a result, the calculator will provide the total duration of all activities, the sum of calories burned and the number of calories consumed for each activity separately, including the time of its execution. The calculator also tells you how many hours you need to constantly perform a given activity to lose weight by about 0.5 kg, taking into account your weight.

CAPM (capital asset pricing model) SML (security market line) 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 calculator in the form of SML allows you to calculate the expected rate of return on all portfolios, not only effective ones, as well as individual stock market shares.

Deltoid, kite concave, dart, arrowhead - diagonals, area, perimeter, sides

Calculate the diagonals of a concave deltoid, kite, side lengths, surface area, perimeter and radius of the inscribed circle. Each size can be calculated using many formulas, just indicate what data we have.

Arithmetic mean of the distribution point series (grouped data)

With this statistical calculator, you will learn how to calculate the arithmetic mean of a distribution point series (grouped data).

Percentage Calculator

using a percentage calculator, you can calculate in a simple and quick way sums, differences, products and percentages .

Ideal gas

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

Spelling words with the phonetic alphabet - converter, translator

Using this translator / converter you can quickly and easily check how to spell each word using the international (and not only) phonetic alphabet.



Online calculator