hugo/docs/content/en/functions/collections/Sort.md

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---
title: collections.Sort
description: Sorts slices, maps, and page collections.
categories: []
keywords: []
action:
aliases: [sort]
related:
- functions/collections/Reverse
- functions/collections/Shuffle
- functions/collections/Uniq
returnType: any
signatures: ['collections.Sort COLLECTION [KEY] [ORDER]']
toc: true
aliases: [/functions/sort]
---
The `KEY` is optional when sorting slices in ascending order, otherwise it is required. When sorting slices, use the literal `value` in place of the `KEY`. See examples below.
The `ORDER` may be either `asc` (ascending) or `desc` (descending). The default sort order is ascending.
## Sort a slice
The examples below assume this site configuration:
{{< code-toggle file=hugo >}}
[params]
grades = ['b','a','c']
{{< /code-toggle >}}
### Ascending order {#slice-ascending-order}
Sort slice elements in ascending order using either of these constructs:
```go-html-template
{{ sort site.Params.grades }} → [a b c]
{{ sort site.Params.grades "value" "asc" }} → [a b c]
```
In the examples above, `value` is the `KEY` representing the value of the slice element.
### Descending order {#slice-descending-order}
Sort slice elements in descending order:
```go-html-template
{{ sort site.Params.grades "value" "desc" }} → [c b a]
```
In the example above, `value` is the `KEY` representing the value of the slice element.
## Sort a map
The examples below assume this site configuration:
{{< code-toggle file=hugo >}}
[params.authors.a]
firstName = "Marius"
lastName = "Pontmercy"
[params.authors.b]
firstName = "Victor"
lastName = "Hugo"
[params.authors.c]
firstName = "Jean"
lastName = "Valjean"
{{< /code-toggle >}}
{{% note %}}
When sorting maps, the `KEY` argument must be lowercase.
{{% /note %}}
### Ascending order {#map-ascending-order}
Sort map objects in ascending order using either of these constructs:
```go-html-template
{{ range sort site.Params.authors "firstname" }}
{{ .firstName }}
{{ end }}
{{ range sort site.Params.authors "firstname" "asc" }}
{{ .firstName }}
{{ end }}
```
These produce:
```text
Jean Marius Victor
```
### Descending order {#map-descending-order}
Sort map objects in descending order:
```go-html-template
{{ range sort site.Params.authors "firstname" "desc" }}
{{ .firstName }}
{{ end }}
```
This produces:
```text
Victor Marius Jean
```
### First level key removal
Hugo removes the first level keys when sorting a map.
Original map:
```json
{
"felix": {
"breed": "malicious",
"type": "cat"
},
"spot": {
"breed": "boxer",
"type": "dog"
}
}
```
After sorting:
```json
[
{
"breed": "malicious",
"type": "cat"
},
{
"breed": "boxer",
"type": "dog"
}
]
```
## Sort a page collection
{{% note %}}
Although you can use the `sort` function to sort a page collection, Hugo provides [sorting and grouping methods] as well.
[sorting and grouping methods]: /methods/pages
{{% /note %}}
In this contrived example, sort the site's regular pages by `.Type` in descending order:
```go-html-template
{{ range sort site.RegularPages "Type" "desc" }}
<h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}
```