| --- |
| page_title: tonumber - Functions - Configuration Language |
| description: The tonumber function converts a value to a number. |
| --- |
| |
| # `tonumber` Function |
| |
| `tonumber` converts its argument to a number value. |
| |
| Explicit type conversions are rarely necessary in Terraform because it will |
| convert types automatically where required. Use the explicit type conversion |
| functions only to normalize types returned in module outputs. |
| |
| Only numbers, `null`, and strings containing decimal representations of numbers can be |
| converted to number. All other values will produce an error. |
| |
| ## Examples |
| |
| ``` |
| > tonumber(1) |
| 1 |
| > tonumber("1") |
| 1 |
| > tonumber(null) |
| null |
| > tonumber("no") |
| Error: Invalid function argument |
| |
| Invalid value for "v" parameter: cannot convert "no" to number: string must be |
| a decimal representation of a number. |
| ``` |