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Log and Antilog Calculator

Use this expanding logarithms calculator to calculate your log and antilog problems. Enter the number and select the base value in the logarithmic functions calculator. Press the Calculate button to get the result of your entered values.

Log and Antilog

Computation of Log

The logarithmic calculator is an antilog calculator as well as a log base calculator because it calculates both log and antilog in one place.

In this space, we will discuss log definition, antilog definition, rules and formula of log, how to find log without logarithm solver, and how to find antilog without inverse log calculator. Keep reading if you are a math geek or just interested in this topic.

What is log?

Wikipedia defines log as,

In mathematics, the logarithm is the inverse function to exponentiation. That means the logarithm of a given number x is the exponent to which another fixed number, the base b, must be raised, to produce that number x.

Logs are ways of expressing a number, it has a base number raised to a power. Logs and antilogs are important components of mathematics and are used in mathematical equations often.

What is antilog?

As the name suggests, antilog is the reverse function of the log. It is used to remove the applied log from a function. Antilog inverses the result of a logarithm function.

Log formula and rules

The formula for log is:

Where b represents the logarithmic base.

The antilog equation can be expressed as:

Here are some of the log rules which are used frequently.

Product

ln(xy) = ln(x) + ln(y)

Quotient

ln(x/y) = ln(x) − ln(y)
Log of power

ln(xy) = yln(x)

Log of exponent

ln(e) = 1

Log of one

ln(1) = 0

Log of reciprocal

ln(1/x) = −ln(x)

Where, ln represents the natural log.

How to calculate log?

Logs can be calculated using the logarithm calculator. Below, we will discuss the manual method to find the log using the logarithm rules.

Example:

Find the log of 256 with base 2.

Solution:

Step 1: Write down and identify the values.

x = 256

b = 2

Step 2: Place the values in the standard log equation.

Step 3: Raise y as the power of the base b and remove the log.

2y = 256

2y = 28

2 is the coefficient on both sides, so they will cancel each other and we will get the value of y.

y = 8

How to calculate antilog?

Want to learn how to find antilog before using an antilog calculator online? Follow the steps below to calculate antilog with an example.

Example:

Find the antilog of 2.5 with base 6.

Solution:

Step 1: Write down and identify the values.

x = 2.5

b = 6

Step 2: Use the antilog equation and place the values.

y = 88.18

Some important antilog values

antilog(2) 102 100
antilog(1) 101 10
antilog(10) 1010 10000000000
antilog2 5 25 32
antilog2 2 22 4
antilog(3) 103 1000
antilog3 5.5 35.5 420.8883
antilog2 1.5 21.5 2.8284
antilog(15.6) 1015.6 3.981071705535E+15
antilog(8) 108 100000000
antilog(0) 100 1
antilog(4) 104 10000
antilog(5) 105 100000
antilog(9) 109 1000000000
antilog(12) 1012 1000000000000
antilog(20) 1020 1.0E+20
antilog(22) 1022 1.0E+22
antilog(13) 1013 10000000000000
antilog(18) 1018 1.0E+18
antilog(5) 105 100000
antilog(14) 1014 1.0E+14

Logarithm Table

Table of base 10, base 2 and base e (ln) logarithms:

x log10 x log2 x loge x
0 undefined undefined undefined
0+ - ∞ - ∞ - ∞
0.0001 -4 -13.287712 -9.210340
0.001 -3 -9.965784 -6.907755
0.01 -2 -6.643856 -4.605170
0.1 -1 -3.321928 -2.302585
1 0 0 0
2 0.301030 1 0.693147
3 0.477121 1.584963 1.098612
4 0.602060 2 1.386294
5 0.698970 2.321928 1.609438
6 0.778151 2.584963 1.791759
7 0.845098 2.807355 1.945910
8 0.903090 3 2.079442
9 0.954243 3.169925 2.197225
10 1 3.321928 2.302585
20 1.301030 4.321928 2.995732
30 1.477121 4.906891 3.401197
40 1.602060 5.321928 3.688879
50 1.698970 5.643856 3.912023
60 1.778151 5.906991 4.094345
70 1.845098 6.129283 4.248495
80 1.903090 6.321928 4.382027
90 1.954243 6.491853 4.499810
100 2 6.643856 4.605170
200 2.301030 7.643856 5.298317
300 2.477121 8.228819 5.703782
400 2.602060 8.643856 5.991465
500 2.698970 8.965784 6.214608
600 2.778151 9.228819 6.396930
700 2.845098 9.451211 6.551080
800 2.903090 9.643856 6.684612
900 2.954243 9.813781 6.802395
1000 3 9.965784 6.907755
10000 4 13.287712 9.210340

References:

  1. How to Calculate Antilog? by sciencing.com
  2. Review of logarithms and antilogarithms - FAQ 1447 - graphpad.com