---
title: "no-nonoctal-decimal-escape"
description: "Disallow the `\\8` and `\\9` escapes in strings"
# Generated by src/codegen/lint-rule-docs.ts. Do not edit below this line.
plugin: "eslint"
aliases: ["eslint/no-nonoctal-decimal-escape"]
kind: "suggestion"
category: "correctness"
default: "warn"
fixable: "suggestion"
typeAware: false
deprecated: false
---

`"\8"` and `"\9"` are the same as `"8"` and `"9"`. The backslash does nothing, so it's either left over or the author meant a real backslash, `"\\8"`.

In strict mode, which includes every ES module, these escapes are a syntax error. The rule matters for scripts and CommonJS files, where they still parse.

The report comes with two suggestions: remove the backslash, which keeps the string's value, or double it. `--fix-suggestions` applies the first.

This rule is on by default.

{/* Generated by src/codegen/lint-rule-docs.ts. Do not edit this section. */}

## Configure

On by default as a warning. To turn it off:

```toml bunfig.toml
[lint.rules]
"no-nonoctal-decimal-escape" = "off" # or "error"
```

{/* End of the generated section. */}

## Examples

Reported, in a file named `release.cjs`:

{/* bad {"filename": "release.cjs"} */}
```js
const version = "v\8.0";
```

Not reported:

{/* good {"filename": "release.cjs"} */}
```js
const version = "v8.0";
const folder = "releases\\8.0";
```