Two figures in, a clear answer out. The 403b calculator uses contribution starts at the age of, planned age of retirement, contribution percentage, contribution percentage, aimed final balance, current 403(b) balance, current salary ^^(required)^^, what would you like to know?, annual salary increase, periodic growth rate, annuity frequency, annual rate of return and one way to produce annual contribution, total annual contribution and length of annuity, applying the standard relationship for this problem in the order the calculation actually needs it.
What Is the 403b Calculator?
The 403b calculator takes contribution starts at the age of, planned age of retirement, contribution percentage, contribution percentage, aimed final balance, current 403(b) balance, current salary ^^(required)^^, what would you like to know?, annual salary increase, periodic growth rate, annuity frequency, annual rate of return and one way and turns them into annual contribution, total annual contribution and length of annuity.
It is the kind of calculation you would otherwise do on the back of an envelope: mechanical, repeatable and easy to get subtly wrong without noticing.
How the 403b Figure Is Built
Each result is calculated from the ones before it, so the working is fully visible. That matters when the answer is going to be quoted to somebody else and you need to be able to explain where it came from.
The figures are exactly as good as the assumptions underneath them. Check the rates, the periods and the tax treatment before you rely on the result.
Reading the Result Sensibly
A small change in an input can move the result by much more than you would expect, particularly where the calculation divides by one of the figures you supplied. That is worth understanding before you rely on a figure.
For anything that will be committed to, write the inputs down beside the result. A number you can reproduce is worth far more than one you cannot explain.
A Worked Example
Working through an example, with contribution starts at the age of set to 10, planned age of retirement set to 5, contribution percentage set to 2, the calculator returns annual contribution of 4, and annual contribution (contr employer) of 200, and total annual contribution of 204. Substitute your own figures and the same steps produce the same kind of answer.
Frequently Asked Questions
What do I need to work out annual contribution?
Enter contribution starts at the age of, planned age of retirement, contribution percentage, contribution percentage, aimed final balance, current 403(b) balance, current salary ^^(required)^^, what would you like to know?, annual salary increase, periodic growth rate, annuity frequency, annual rate of return and one way. The calculator then works through the relationship and reports annual contribution, total annual contribution and length of annuity.
What does the 403b actually calculate?
It takes contribution starts at the age of, planned age of retirement, contribution percentage, contribution percentage, aimed final balance, current 403(b) balance, current salary ^^(required)^^, what would you like to know?, annual salary increase, periodic growth rate, annuity frequency, annual rate of return and one way and converts them into annual contribution, total annual contribution and length of annuity using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.
How should I enter contribution starts at the age of?
Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.
Is the answer exact?
It is as exact as the formula and the inputs allow. The method itself is the standard one for this problem, so the only sources of error are the figures you enter and the precision you ask for.
Do I have to fill in every field?
Only the fields a particular result depends on. If you leave one blank, the results that need it simply show a note instead of a number, and everything else still works.