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Using log and antilog is very common in mathematical calculations. So, users may have to calculate log and antilog in Excel also. To make long, monotonous calculations simple, we have to use the log, and to go back to original values we have to use antilog. Excel has some dedicated Log functions to use but no Antilog functions. Also in mathematics, there is no symbol for the antilog operator. So, in this article, I will give brief explanations of log and antilog and show how to calculate Antilog in Excel.

## What Is the Log of a Number?

In brief, it is the power or exponent at which a base value will be raised to be equal to a given number. In an example, we know 103=1000 which means 1000 is equal to the 3rd power of base 10. With logarithm, it will be like, Log10(1000) = 3. Here, 10 is the base value. And, 1000 is the product, and 3 is the power or exponent.

So, it can be said that Log gives the power of a base value to make the number. The format is as follows:

Normal Format:

AB=C

In Log Format:

LogAC=B

So, if you ask how many times you have to multiply A to make the value of B  then you have to do LogAC or you have to multiply A for B times to make C. this is why we use Log in mathematics.

## Relation between Log and Antilog

Antilog in mathematics will do the inverse work of log. So, Antilog will give the value of the product of n time multiplication of base a. For an example:

Normal Format:

LogAB = C

In Antilog:

AC= B

So, antilog is nothing but the power product for the base value.

With a Numerical Example:

Log101000 = 3

With Antilog :

103 = 1000

So, you have seen the relationship between the Log and Antilog above. And you understand that to get the value of antilog of a number of any base is nothing but the power equal to the number of the base. And, in Excel, to call the power operator, we have to use the exponent operator (^). For example, 103  will be written in Excel as 10^3.

Suppose, here you have some numbers in an Excel file, and you have to calculate the Log values of the numbers and then calculate the Antilog of logs so you will get the number back. Here I will show you how to calculate antilog for base 10, base e, and for any random bases in Excel. ### Type 1: Calculate Antilog for Base 10

In most cases, Log is used for base 10. And in general, where no base value is mentioned, you can assume it as base 10. In Excel, it has an inherent LOG10 function to calculate the log of base 10. But it has no functions to make antilog values. For this, you have to write a manual formula.  Follow the steps below:

Steps:

• At first, to calculate the value of base 10 log of the number in cell B4, input this formula into cell C4.
`=LOG10(B4)`
• LOG10 is a function that returns the logarithmic value of a number for base 10. • Now, use the fill handle icon to drag the formula to other cells. • As there is no function to calculate antilog in Excel, so we have to insert manual formula.
• So, write this formula in cell D4.
`=10^C4` • Then, you get the number back as an antilog.
• Finally, use the Fill Handle icon to copy and paste the formula to other cells. • So, if you make a log of a number and do antilog again then you will get the number back.

Read More: How to Calculate Logarithmic Growth in Excel

### Criteria 2: Calculate Antilog for Base ‘e’

Another most used logarithmic function is log-based e or Ln. When you take the base as exponential operator e, then this becomes Natural Log or Ln. And, in Excel, there is a default function to calculate Ln values, and also antilog values. Which is the LN function. Follow the steps below:

Steps:

• At first, write this formula into the cell C4, to get the Ln values:
`=LN(B4)` • Now, to calculate the antilog of Ln values, we will use the EXP function.
• Insert this formula into cell D4.
`=EXP(C4)` • Then, use the fill handle icon to drag the formula to the other cells also. • Now, you have the antilog values of the Ln values.
• Also, the antilog values are the same as the main numbers.

Read More: How to Calculate Natural Logarithm in Excel

### Criteria 3: Calculate Antilog for a Random Base

Sometimes, you have to calculate log and antilog values of numbers for any bases except 10 or e. And to calculate this, in Excel, you will find the LOG function. But to calculate the antilog value, you have to write a manual formula. Follow the steps below:

Steps:

• Suppose you want to calculate the log value of base 5 for the number cell B4.
• Then, insert this formula into the cell C4:

`=LOG(B4,5)` • Now to calculate the antilog value of cell C5, insert this formula into cell D5.
`=5^C4` • Finally, use the Fill Handle icon to drag the formula to the other cells • As a result, now you have the values of antilog which are equal to the numbers.
• You can use any base in place of 5 here.

Read More: How to Calculate Log Base 2 in Excel

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