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

# Functions

## String Functions

* [`apply-codecs()`](/flat/reference/functions/apply-codecs.md)
* [`base64-decode()`](/flat/reference/functions/base64-decode.md)
* [`base64-encode()`](/flat/reference/functions/base64-encode.md)
* [`capitalize-first()`](/flat/reference/functions/capitalize-first.md)
* [`concat()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/concat)
* [`contains()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/contains)
* [`ends-with()`](/flat/reference/functions/ends-with.md)
* [`join()`](/flat/reference/functions/join.md)
* [`matches()`](/flat/reference/functions/matches.md)
* [`md5()`](/flat/reference/functions/md5.md)
* [`normalize-space()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/normalize-space)
* [`replace()`](/flat/reference/functions/replace.md)
* [`split()`](/flat/reference/functions/split.md)
* [`starts-with()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/starts-with)
* [`string()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/string)
* [`string-length()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/string-length)
* [`substring()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/substring)
* [`substring-after()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/substring-after)
* [`substring-before()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/substring-before)
* [`tolower()`](/flat/reference/functions/tolower.md)
* [`toupper()`](/flat/reference/functions/toupper.md)
* [`translate()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/translate)
* [`trim()`](/flat/reference/functions/trim.md)
* [`urldecode()`, `url-decode()`](/flat/reference/functions/urldecode.md)
* [`urlencode()`, `url-encode()`](/flat/reference/functions/urlencode.md)

## JSON Functions

* [`json-doc()`](/flat/reference/functions/json-doc.md)
* [`json-parse()`](/flat/reference/functions/json-parse.md)
* [`json-stringify()`](/flat/reference/functions/json-stringify.md)
* [`json-to-csv()`](/flat/reference/functions/json-to-csv.md)
* [`json-to-xml()`](/flat/reference/functions/json-to-xml.md)
* [`jwt-decode()`](/flat/reference/functions/jwt-decode.md)
* [`jwt-encode()`](/flat/reference/functions/jwt-encode.md)
* [`xml-to-json()`](/flat/reference/functions/xml-to-json.md)

## Array Functions

* [`array()`](/flat/reference/functions/array.md)
* [`array-reverse()`](/flat/reference/functions/array-reverse.md)
* [`sort()`](/flat/reference/functions/sort.md)

## Boolean Functions

* [`boolean()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/boolean)
* [`false()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/false)
* [`not()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/not)
* [`true()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/true)

## Math Functions

* [`ceiling()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/ceiling)
* [`floor()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/floor)
* [`number()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/number)
* [`round()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/round)
* [`sum()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/sum)

## Date Functions

* [`unixtime()`](/flat/reference/functions/unixtime.md)

## Encryption and Signature Functions

* [`calc-signature`](/flat/reference/functions/calc-signature.md)
* [`decrypt`](/flat/reference/functions/decrypt.md)
* [`decrypt-xml`](/flat/reference/functions/decrypt-xml.md)
* [`encrypt`](/flat/reference/functions/encrypt.md)
* [`verify-signature`](/flat/reference/functions/verify-signature.md)
* [`verify-xmldsig`](/flat/reference/functions/verify-xmldsig.md)

## Other Functions

* [`body()`](/flat/reference/functions/body.md)
* [`content()`](/flat/reference/functions/content.md)
* [`count()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/count)
* [`file-exists()`](/flat/reference/functions/file-exists.md)
* [`fit-document()`](/flat/reference/functions/fit-document.md)
* [`fit-log()`](/flat/reference/functions/fit-log.md)
* [`fit-serialize()`](/flat/reference/functions/fit-serialize.md)
* [`get-log()`](/flat/reference/functions/get-log.md)
* [`has-class()`](/flat/reference/functions/has-class.md)
* [`html-parse()`](/flat/reference/functions/html-parse.md)
* [`id()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/id)
* [`ldap-lookup()`](/flat/reference/functions/ldap-lookup.md)
* [`ldap-query()`](/flat/reference/functions/ldap-query.md)
* [`lang()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/lang)
* [`last()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/last)
* [`local-name()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/local-name)
* [`lookup()`](/flat/reference/functions/lookup.md)
* [`name()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/name)
* [`namespace-uri()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/namespace-uri)
* [`position()` ↗](https://developer.mozilla.org/en-US/docs/web/XPath/Functions/position)
* [`uuid3()` and `uuid4()`](/flat/reference/functions/uuid.md)
* [`xml-parse()`](/flat/reference/functions/xml-parse.md)