# PHP Math - log10() Function

The PHP Math log10() function returns the base-10 logarithm of a given number. In special cases it returns the following:

• If the argument is NAN or less than zero, then the result is NAN.
• If the argument is positive infinity, then the result is positive infinity.
• If the argument is zero, then the result is negative infinity.

### Syntax

```log10(number)
```

### Parameters

 `number` `Required. ` Specify the number.

### Return Value

Returns the base-10 logarithm of a given number.

### Example:

In the example below, log10() function is used to calculate the base-10 logarithm of a given number.

```<?php
echo "log10(0) = ".log10(0)."\n";
echo "log10(0.5) = ".log10(0.5)."\n";
echo "log10(1) = ".log10(1)."\n";
echo "log10(10) = ".log10(10)."\n";
echo "log10(100) = ".log10(100)."\n";
echo "log10(INF) = ".log10(INF)."\n";
echo "log10(-INF) = ".log10(-INF)."\n";
echo "log10(NAN) = ".log10(NAN)."\n";
?>
```

The output of the above code will be:

```log10(0) = -INF
log10(0.5) = -0.30102999566398
log10(1) = 0
log10(10) = 1
log10(100) = 2
log10(INF) = INF
log10(-INF) = NAN
log10(NAN) = NAN
```

❮ PHP Math Functions

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