This is a step-by-step guide to converting a binary number to denary. In this example, we will convert 10101010 to denary.
Step 1: Draw Your Binary Place Values
Draw a table which is eight columns wide. This will hold our binary place values.
You may find it easier to start with the column on the right and put "1" into it. Each value doubles as we move to the left.
| 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|
Step 2: Write your Binary Number into the Table
Write your binary number into the table. Remember to include all the digits.
Our binary number is 10101010.
| 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
Step 3: Add Columns with a 1
Where the binary number is a 1, look at the binary placeholder above it.
Add up the placeholder values where the binary value is 1.
128 + 32 + 8 + 2 = 170
| 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |