---
url: /docs/guide/usage/linter/rules/eslint/radix.md
---

### What it does

Enforce the consistent use of the radix argument when using `parseInt()`,
which specifies what base to use for parsing the number.

### Why is this bad?

Using the `parseInt()` function without specifying
the radix can lead to unexpected results.

See the
[MDN documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt#radix)
for more information on how `parseInt()` handles certain edge-cases.

### Configuration

Note that passing an option to this rule has no effect on its behavior.
In v1.49.0, the config option for this rule was removed and made a no-op.
This matches the behavior change made in ESLint v10, and the rule now
always enforces that a radix parameter is provided to `parseInt()`.

If you receive new violations due to this change, you may either opt
to disable this rule, or add the radix parameter to all usages of
`parseInt()` in your codebase.

### Examples

Examples of **incorrect** code for this rule:

```javascript
let num = parseInt("071"); // 57
```

Examples of **correct** code for this rule:

```javascript
let num = parseInt("071", 10); // 71
```

## Configuration

This rule accepts one of the following string values:

### `"always"`

Always require the radix parameter when using `parseInt()`.

### `"as-needed"`

Only require the radix parameter when necessary.

## How to use

## Version

This rule was added in v0.3.3.

## References