Taking the antilog reverses a logarithm. It turns pH back into hydrogen ion concentration, decibels back into intensity ratios and log-transformed statistics back into original units.
How to use the Antilog Calculator
- Logarithm base
- Custom base
- Logarithm value y
Results update as you type, and everything is calculated in your browser.
How it works
Choose the base and enter the logarithm y.
Inputs explained
| Field | What to enter |
|---|---|
| Logarithm base | Choose one: 10 (common log), e (natural log), 2 (binary log), Custom base |
| Custom base | A number |
| Logarithm value y | A number |
Example values
How the main result changes when Custom base changes and everything else stays at the example values above:
| Custom base | Antilog x = bʸ |
|---|---|
| 2.5 | 316.2278 |
| 3.75 | 316.2278 |
| 5 | 316.2278 |
| 6.25 | 316.2278 |
| 7.5 | 316.2278 |
| 10 | 316.2278 |
Formula
antilog_b(y) = bʸ
Worked example
Inputs — Logarithm base: 10 (common log); Logarithm value y: 2.5.
Results — Antilog x = bʸ = 316.227766016838; Order of magnitude (log₁₀ x) = 2.5.
Key terms
- Antilogarithm
- The number whose logarithm is given.
Frequently asked questions
What is the antilog of 2 (base 10)?
100.
What is the antilog of 1 in base e?
e ≈ 2.71828.
How do I get [H⁺] from pH?
[H⁺] = 10^(−pH) mol/L.
Is antilog the same as exponent?
Yes – antilog_b(y) = bʸ.