> For the complete documentation index, see [llms.txt](https://daseldocs.tomwright.me/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://daseldocs.tomwright.me/functions/indexof.md).

# indexOf

Returns the index of the first occurrence of a substring within a string. Returns `-1` if the substring is not found.

#### Syntax

```
indexOf(input, substring)
```

or chained:

```
<string>.indexOf(substring)
```

#### Arguments

* **input** (`string`, optional when chained) - The string to search in.
* **substring** (`string`) - The substring to search for.

#### Examples

**Find a substring**

```
indexOf("hello world", "world")
// 6
```

**Chained usage**

```
"foobar".indexOf("bar")
// 3
```

**Not found**

```
"hello".indexOf("xyz")
// -1
```

**CLI usage**

```bash
$ echo '{"path": "/api/v2/users"}' | dasel -i json 'path.indexOf("/v2")'
4
```

**Check if a substring exists**

```
"hello world".indexOf("world") >= 0
// true
```


---

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