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LOG
LOG returns the logarithm of a number with any base you specify; if you omit the base it defaults to 10. Use it to convert exponential data to a linear scale, compute decibels, or solve exponential equations.
Excel
=LOG(A2,2)Google Sheets
=LOG(A2,2)✓
Verified example
Computed by a real spreadsheet engine on the sample data below.
| Value | Log Base 2 |
| 1 | |
| 2 | |
| 8 | |
| 64 |
=LOG(A2,2)→0
Try it with your data
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Sample data — click any cell to edit
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How it works
- 1A2 is the number whose logarithm you want — it must be a positive value.
- 22 is the base of the logarithm (binary log in this case).
- 3LOG(8,2) returns 3 because 2^3 = 8.
Need a version for your data?
Try: “Calculate the base-2 logarithm of numbers to measure data in bits”