The string library provides generic functions to manipulate strings, such as
to extract substrings or match patterns. You can access the string library by
the global `Library.string` library.

See
[String pattern reference](/luau/strings#string-pattern-reference)
for details on using `Library.string.match()`, `Library.string.gmatch()`, and
`Library.string.gsub()` to find (and replace) substrings.


Returns the internal numerical codes of the characters
`s[i], s[i+1], ..., s[j]`. The default value for `i` is 1; the default
value for `j` is `i`. These indices are corrected following the same rules
of function `Library.string.sub()`.


string.byte

Returns the internal numerical codes of the characters
`s[i], s[i+1], ..., s[j]`. The default value for `i` is 1; the default
value for `j` is `i`. These indices are corrected following the same rules
of function string.sub.


Receives zero or more integers and returns a string with length equal to
the number of arguments, in which each character has the internal
numerical code equal to its corresponding argument.


string.char

Searches for the first occurrence of a pattern in a string and returns the
start and end indices of the match. If no match is found, it returns
`nil.` You can specify where to start the search using the optional `init`
parameter which defaults to 1 and can be negative. An optional `plain`
parameter turns off pattern matching, so the function performs a plain
substring search; note that if you use `plain`, you must also provide
`init.`

```lua
-- Example 1: Basic usage
local s = "Hello, world!"
local pattern = "world"
local start_index, end_index = string.find(s, pattern)
print(start_index, end_index)  -- Output: 8 12
```

```lua
-- Example 2: Using init parameter
local s = "Hello, world! Hello, Roblox!"
local pattern = "Hello"
local start_index, end_index = string.find(s, pattern, 10)
print(start_index, end_index)  -- Output: 15 19
```

```lua
-- Example 3: Using plain parameter
local s = "Hello, world! (Hello)"
local pattern = "(Hello)"
local start_index, end_index = string.find(s, pattern, 1, true)
print(start_index, end_index)  -- Output: 14 20
```

```lua
-- Example 4: No Pattern found
local s = "Hello, world!"
local pattern = "Roblox"
local start_index, end_index = string.find(s, pattern)
print(start_index, end_index)  -- Output: nil
```


string.find

pattern

The pattern to search for in given string.


init

plain

Looks for the first match of pattern in the string `s` and returns the
indices of `s` where the occurrence starts and ends.


Returns a formatted version of its variable number of arguments following
the description given in its first argument, which must be a string.

You can convert variables into user-friendly strings of text using the
`Library.string.format()` function. The function requires the following
format:

`%[flags][width].[precision][specifier]`.

#### Specifiers

The most important part of string formatting is the **specifiers**.

<table>
  <thead>
    <tr>
      <th>Specifier</th>
      <th>Accepts</th>
      <th>Outputs</th>
      <th>Example Output</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td><code>c</code></td>
      <td>integer</td>
      <td></td>
      <td>3</td>
    </tr>
    <tr>
      <td><code>d</code> or <code>i</code></td>
      <td>integer</td>
      <td>Decimal representation.</td>
      <td> 321 </td>
    </tr>
    <tr>
      <td><code>e</code> or <code>E</code></td>
      <td>float</td>
      <td>Scientific notation using <code>e</code> or <code>E</code>.</td>
      <td>3.296e2<br>3.296E2</td>
    </tr>
    <tr>
      <td><code>f</code></td>
      <td>float</td>
      <td></td>
      <td>3231.1231</td>
    </tr>
    <tr>
      <td><code>g</code> or <code>G</code></td>
      <td>float</td>
      <td>The shorter of <code>e</code>/<code>E</code> and <code>f</code>.</td>
      <td>3E14<br>3e14</td>
    </tr>
    <tr>
      <td><code>o</code></td>
      <td>integer</td>
      <td>Octal representation.</td>
      <td>610</td>
    </tr>
    <tr>
      <td><code>q</code></td>
      <td>string</td>
      <td>String in a form suitable to be safely read back by the Luau interpreter. The string is written between double quotes and all double quotes, new lines, embedded zeros, and backslashes are correctly escaped.</td>
      <td>"print(\"Hi\")"</td>
    </tr>
    <tr>
      <td><code>s</code></td>
      <td>string</td>
      <td></td>
      <td>Hello world!</td>
    </tr>
    <tr>
      <td><code>u</code></td>
      <td>integer</td>
      <td>Decimal representation.</td>
      <td>3131</td>
    </tr>
    <tr>
      <td><code>x</code> or <code>X</code></td>
      <td>integer</td>
      <td>Hexadecimal representation.</td>
      <td>7fa<br>7FA</td>
    </tr>
    <tr>
      <td><code>*</code></td>
      <td>any</td>
      <td>Equivalent to <code>s</code> but accepts any variable by converting it to a string using <code>Global.LuaGlobals.tostring()</code>.</td>
      <td>table: 0x0123456789abcdef</td>
    </tr>
    <tr>
      <td><code>%</code></td>
      <td></td>
      <td><code>%</code> followed by another <code>%</code> will return the <code>%</code> sign itself.</td>
      <td>%</td>
    </tr>
  </tbody>
</table>

```
local str = "The magic word is %s"
print(string.format(str, "Roblox"))
-- The magic word is Roblox

local str = "The magic word is %q"
print(string.format(str, "Roblox"))
-- The magic word is "Roblox"

local str = "Skip to \na new line and \nanother new line!"
print(string.format(str, "%q"))
--[[ Output:
Skip to
a new line and
another new line!
]]
```

#### Flags

<table>
<thead>
  <tr>
    <th>Flag</th>
    <th>Description</th>
  </tr>
</thead>
<tbody>
  <tr>
    <td><code>-</code></td>
    <td>Left-justify the given field width (see <code>Width</code> below). Right justification is the default.</td>
  </tr>
  <tr>
    <td><code>+</code></td>
    <td>Forces a "+" sign to precede a number. Has no effect on negative numbers.</td>
  </tr>
  <tr>
    <td>(space)</td>
    <td>One blank space is inserted before a positive number, while negative numbers are unaffected. This is useful for making positive and negative numbers vertically align in a visual stacked list.</td>
  </tr>
  <tr>
    <td><code>#</code></td>
    <td>When used with <code>o</code> and <code>x</code>/<code>X</code>, writes a 0 (octal) or 0x/0X (hex) before values other than zero.<br>When used with <code>e</code>/<code>E</code> and <code>f</code>, forces the output to contain a decimal point, even if no digits would follow (by default, no decimal point is written if no digits follow).<br>When used with <code>g</code> or <code>G</code>, the result is the same as with <code>e</code> or <code>E</code> but trailing zeros are not removed.</td>
  </tr>
  <tr>
    <td><code>0</code></td>
    <td>Left-pads the number with zeros instead of empty spaces (see <code>Width</code> below).</td>
  </tr>
</tbody>
</table>

```lua
local str = "%-10d"
print(string.format(str, 300) .. "]")
-- 300       ]
-- There are 7 spaces between '300' and ']'

local str = "%+i versus %+i"
print(string.format(str, 300, -300)) -- +300 versus -300

local str = "There is a% i%% chance of rain in Seattle today."
print(string.format(str, 100))
-- There is a 100% chance of rain in Seattle today.
```

#### Width

<table>
  <thead>
    <tr>
      <th>Width</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>(number)</td>
      <td>Minimum number of characters to return. If the number of characters to be formatted is less than this number, the result is padded with blank spaces.</td>
    </tr>
  </tbody>
</table>

```lua
local str = "%012i"
print("Score: " .. string.format(str, 15000))
-- Output: Score: 000000015000
-- The output has 12 digits total, left-padded with zeros
```

#### Precision

The default precision is 1. If you give a period without a value, the
default is 0.

<table>
  <thead>
    <tr>
      <th>Precision</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td><code>.</code>(number)</td>
      <td>For integer specifiers (<code>d</code>, <code>i</code>, <code>o</code>, <code>u</code>, <code>x</code>/<code>X</code>), precision specifies the minimum number of digits to be returned. If the value to be formatted is shorter than this number, the result is padded with leading zeros. A precision of 0 means that no character is written for the value 0.<br>For <code>e</code>/<code>E</code> and <code>f</code> specifiers, this is the number of digits to be printed after the decimal point.<br>For <code>g</code>/<code>G</code> specifiers, this is the maximum number of digits (before the <code>e</code>/<code>E</code>, if present).<br>For <code>s</code>, this is the maximum number of characters to be returned.<br>For <code>c</code> and <code>q</code>, this has no effect.</td>
    </tr>
  </tbody>
</table>

```lua
-- Add decimal with precision of 2 for a currency output
local str = "$%.2f"
print(string.format(str, 300)) -- Output: $300.00

-- Return first 6 letters of a string
local str = "%.6s"
print(string.format(str, "Robloxian")) -- Output: Roblox

local str = "Once upon a time, there was a dragon named %s and it had %.8f horns."
print(string.format(str, "Pi", math.pi))
-- Output: Once upon a time, there was a dragon named Pi and it had 3.14159265 horns.
```


string.format

formatstring

Returns a formatted version of its variable number of arguments following
the description given in its first argument, which must be a string.


Returns an iterator function that returns the next captures from pattern
over the string `s` each time it's called.


string.gmatch

Short for global substitution. Returns a copy of `s` in which all (or the
first n, if given) occurrences of the pattern are substituted (replaced)
with the given `replacement`. The second value returned is the total
number of substitutions made.

The `replacement` can be one of several types, each used differently to
determine the actual string:

- string: The pattern is replaced with the string directly
- table: The string that matched the pattern is looked up in the table as
  a key, and the value (string) is what replaces it, if it exists.
- function: Called with the string that matched the pattern, should return
  the string to replace the matched pattern.

An optional final argument can be provided which specifies the maximum
number of substitutions to make (for example, stop after 2 replacements)

#### Various Examples

```lua
-- Basic replacement
string.gsub("I love tacos!", "tacos", "Roblox") --> I love Roblox! 1
-- Replacement with a pattern
string.gsub("I like red!", "%w+", "word") --> word word word! 3
-- Replacement table
string.gsub("I play Roblox.", "%w+", {I="Je", play="joue à"}) --> Je joue à Roblox. 3
-- Replacement function
string.gsub("I have 2 cats.", "%d+", function(n) return tonumber(n) * 12 end) --> I have 24 cats. 1
-- Replace only twice
string.gsub("aaa", "a", "b", 2) --> bba 2
-- Replacement with capture groups (maximum of nine)
string.gsub("love2play Roblox", "(%w+)(%d+)(%w+)%s+(%w+)", "I %1 %2 %3 %4!") --> I love 2 play Roblox! 1
```


string.gsub

The string whose occurrences of the given pattern shall be replaced.


replacement

Determines what should replace the occurrence(s) of the given pattern.


replacements

The maximum number of substitutions to make.


Returns a copy of `s` in which all or the first `n` occurrences of the
pattern are replaced with the given replacement. The second value returned
is the total number of substitutions made.


string.len

Returns a copy of a string with all uppercase letters changed to
lowercase.


string.lower

Looks for the first match of pattern in the string `s`. If a match is
found, it is returned; otherwise, it returns `nil`. A third, optional
numerical argument, init, specifies where to start the search; its default
value is 1 and can be negative.


string.match

Looks for the first match of pattern in the string `s`. If a match is
found, it is returned; otherwise, it returns `nil`. A third, optional
numerical argument, init, specifies where to start the search.


Returns a binary string containing the provided arguments. The first
argument, `format`, determines the way the remaining arguments are packed;
see [here](https://www.lua.org/manual/5.3/manual.html#6.4.2) for options.


string.pack

format

Returns a binary string containing the provided arguments.


Returns the size in bytes of any string packed with a given description.
The sole argument, `format`, determines the way the remaining arguments
are packed, but you cannot use `s` and `z` because they have variable
lengths. See [here](https://www.lua.org/manual/5.3/manual.html#6.4.2) for
options.


string.packsize

Returns the size in bytes of any string packed with a given description.


Returns a string that is the concatenation of `n` copies of the string
`s`.


string.rep

Returns a string that is the string `s` reversed.


string.reverse

Splits a string into parts based on the defined separator character(s),
returning a table of ordered results.

If an empty "slice" is located, that part will be returned as an empty
string. For instance `string.split("abc||def", "|")` will return a table
with three strings: `"abc"`, `""`, and `"def"`.

```lua
local values = input:split(",")
print(values[1], values[2], values[3])
```

Also note that whitespace from the original string will be preserved, for
example `string.split("abc _ def", "_")` will honor the whitespace on both
sides of the `_` separator. By default, the separator character is `,` but
you can specify an alternative character or series of characters.

**Corner Cases**

#### Empty String

```lua
"" --> ""
```

#### Empty Slices

```lua
"foo,,bar" --> "foo", "", "bar"
",foo" --> "", "foo"
"foo," --> "foo", ""
"," --> "", ""
",," --> "", "", ""
```

#### Whitespace Preserved

```lua
"   whitespace   " --> "   whitespace   "
"foo , bar" --> "foo ", " bar"
```

#### Invalid UTF-8

```lua
"\xFF" --> "\xFF"
"\xFD,\xFE" --> "\xFD", "\xFE"
```

#### Unicode

```lua
"，" --> U+FF0C FULLWIDTH COMMA
"我很高兴，你呢？" --> "我很高兴", "你呢？"
"•" --> U+2022 BULLET
"hello•world" --> "hello", "world"
```


string.split

separator

The separator character(s) to be used for splitting the string.


Splits a string into parts based on the defined separator character(s),
returning a table of ordered results.


Returns the substring of `s` that starts at `i` and continues until and
including `j`. `i` and `j` can be negative. `i` defaults to 1 and `j`
defaults to `-1`.


string.sub

Extracts the values packed in the provided binary string based on the
first argument, `format`, which should match the one originally used to
`Library.string.pack|pack()` the string; see
[here](https://www.lua.org/manual/5.3/manual.html#6.4.2) for options. The
optional third parameter determines the byte at which the reading starts.


string.unpack

data

readStart

The values packed into the provided binary string, plus the index of
the first unread byte.


Extracts the values packed in the provided binary string.


Returns a copy of a string with all lowercase letters changed to
uppercase.


string.upper

string

Provides generic functions to manipulate strings.


An object that runs connected functions upon a specific occurrence.

Data Type

RBXScriptSignal

Luau

Tuple

Variant

Data type having a value of either true or false.

boolean

Functions are blocks of code that can execute multiple times on command.

function

A double-precision floating-point number.

number

A sequence of characters, such as letters, numbers, and symbols.

Data type which can store multiple values of any non-nil type, including booleans, numbers, strings, functions, and other tables.

table

Experiences

Avatar

Assets

Samples and projects

Engine API

Open Cloud API

Studio

Analytics

Platform

Tutorials

Creator programs

Education

Courses

Learn

This method is asynchronous and returns an `Operation`, which represents the current state of the operation. It contains an endpoint path that you can poll to obtain the real response and applicable metadata. See the [documentation]({longRunningOperationsLink}) on long-running operations for more information.
            
The following sections describe the response and metadata objects that are provided when an operation completes.

Beta endpoints are ready for public use. Breaking changes are possible but rare.

These Open Cloud documentation pages will be removed on March 31, 2026. You will be automatically redirected to the new Open Cloud documentation at that time. {linkStart}Learn more{linkEnd}

These old Open Cloud pages will be removed and redirected on March 31, 2026. {linkStart}Learn more{linkEnd}

Experimental endpoints are ready for public use, but may experience breaking changes occasionally as the API contract is finalized.

This endpoint can be called in-experience through {httpServiceLinkStart}HttpService{httpServiceLinkEnd} with an API key.

This field may be set when creating a resource, but may not be modified by subsequent requests.

These fields may be set when creating a resource, but may not be modified by subsequent requests.

This field may be provided in requests, but will never be included in responses.

Legacy authentication method. Always prefer using API Key or OAuth 2.0 when available.

Per API Key: {maxInPeriod} requests every {periodInSeconds} seconds per IP Address

Requires no authentication to call. Typically has significantly lowered rate limits. Always prefer using API Key or OAuth 2.0 when available.

For each grouping, only one of the following fields in the schema has to be provided, the remaining can be excluded.

You can opt back in at any time. {linkStart}Provide feedback.{linkEnd}

You are viewing the old docs. {linkStart}Provide feedback.{linkEnd}

You can opt out at any time and be redirected back to the old reference pages. {linkStart}Provide feedback.{linkEnd}

You are viewing the revamped docs. {linkStart}Provide feedback.{linkEnd}

This field may be set on responses, but will be ignored in requests.

Note: Rate limits can be lower during high-traffic periods. Certain endpoints have additional rate limits. [Learn more about rate limits]({link}).

{limit} requests per day across all API keys for a user or group

{limit} requests per hour across all API keys for a user or group

{limit} requests per minute across all API keys for a user or group

{limit} requests per second across all API keys for a user or group

{limit} requests per minute per API key owner

{limit} request(s) per second per API key owner

Scopes control what permissions your credentials have. Your credentials can only access the endpoints supported by the scopes you selected.

Stable endpoints are production-ready and will almost never experience breaking changes during their lifetime.

This target enables you to limit your key's access to selected {requiredParts}

This target enables you to limit your key's access to selected {requiredParts} and {optionalParts}

Target types are used to restrict the resources that your credentials have permissions on. Only the selected resources can be acted on even if your account has permissions on additional resources. Some scopes do not have target parts. In these cases, all of your relevant resources can be acted on.

The universe Top Level Part does not need to be selected for user-owned API Keys. In this case, your API Key will have access to all of your user-owned experiences and group-owned experiences that you have the right group permissions on.

Try It Out is not yet supported for endpoints requiring API key or OAuth 2.0 authentication

Cookie authentication is disabled for high risk operations for safety.

Critical risk endpoints are extremely sensitive and Try It Out is disabled for safety

Note: Authentication headers are not included in this code sample. You may need to add an authentication header for this command to work.

This is a high risk endpoint that can modify or delete critical data. Use extreme caution when testing.

This API endpoint has been classified as HIGH RISK and may affect live data or user accounts.

Authenticated requests to high-risk APIs can make changes that cannot be undone. Please review your request parameters carefully before proceeding.

Please login to use cookie authentication

This is a low risk endpoint that retrieves data. This is generally safe to test.

This is a medium risk endpoint that modifies data. Test carefully with non-critical accounts, as changes may be permanent.

To keep your account safe, never paste text here from other sources or send information from this page to others.

You are about to test live API endpoints using your actual account credentials.

Only proceed if you understand the implications of the API calls you're about to make. Review the API documentation carefully before testing.

API calls will be made using your authenticated session

These are real API calls that may affect your account or data

Rate limits and other API restrictions apply

Some operations may modify or delete data

This endpoint has been superseded by these recommended alternative endpoints:

The following scopes are required to call this endpoint. For more
information on generating proper keys, see [Manage API keys]({apiKeyReferenceDocLink}).

For more information on generating keys, see [Manage API keys]({apiKeyReferenceDocLink}).

The following endpoints are available at paths relative to the base URL.

This string is formatted as a [FieldMask](/cloud/reference/types#fieldmask).

A JSON value can be `null`, `boolean`, `string`, `number`, `array`, or `object`.

The following scopes are required for your OAuth 2.0 application to use this endpoint. For more information on how to register an OAuth 2.0 application, see [App registration and review]({oauth2ReferenceDocLink}).

For more information on how to register an OAuth 2.0 application, see [App registration and review]({oauth2ReferenceDocLink}).

The following objects describe payloads that are accepted or returned. See each individual endpoint for more information on when these objects are used.

The following scopes are required to call this endpoint.

Resource Paths

This string is formatted as a [Timestamp](/cloud/reference/types#timestamp).

The following scopes are required for your OAuth 2.0 application to use this endpoint. For more information on how to register an OAuth 2.0 application, see [App Registration and Review]({oauth2ReferenceDocLink}).

Not Recommended

You are viewing the revamped Open Cloud reference.

You've opted out of the new Open Cloud reference.

View your ad campaigns and their performance.

Create, update, and manage your ad campaigns.

This allows viewing information about your assets.

This allows uploading and updating assets to Roblox.

This allows viewing asset permissions for subjects (including groups and experiences) and assets your account has access to.

This allows granting asset permissions to any subjects (including groups and experiences) and assets your account has access to.

This allows you to view the status and results of avatar auto-setup jobs on your behalf.

This allows you to create and manage avatar auto-setup jobs on your behalf.

Grants the ability to update badges owned by the user.

This allows viewing information about your commerce items.

This allows making changes to your synced commerce items.

This allows viewing information about your commerce merchant connections.

This allows editing of your commerce merchant connections.

This allows you to view information about your Creator Store products.

This allows you to modify information about your Creator Store products.

This allows you to view information about your Creator Store saves.

This allows you to modify information about your Creator Store saves.

Grants access to create data stores on your behalf.

Grants access to delete data stores on your behalf.

Grants access to read a list of data stores.

Grants access to take a snapshot of your data stores.

Grants access to create entries in your data stores.

Grants access to mark specified entries for deletion.

Grants access to list your data store's entries.

Grants access to read specified entries in your data stores.

Grants access to update the value, attributes, and users of an entry.

Grants access to delete revisions of your data store's entries.

Grants access to list revisions for your data store's entries.

Grants access to read revisions of your data store's entries.

Grants access to view configuration details for the authorized user's developer products.

Grants access to edit the authorized user's developer products.

This allows viewing information about your universe's environments.

This allows editing of your universe's environments.

Grants access to view configuration details for the authorized user's game passes.

Grants access to edit the authorized user's game passes.

Grants access to view community forums information for your account.

Grants access to manage community forums information for your account.

This allows viewing information about your communities.

This allows you to manage community join requests and role updates of lower-ranked community members for your account.

Allows you to view an instance's property data.

Allows you to modify the property data of instances (currently only supports Scripts).

This allows viewing information about your inventory.

Grants access to manage your badges and spend Robux.

Grants access to update the authorized user's badges.

Grants access to manage your developer products.

Grants access to read information about the experiences you have notifications on for.

Grants access to turn on or off notifications for experiences on your behalf.

Grants access to manage your communities.

Grants permission to read community information.

Grants access to read and write your localization tables

Grants access to manage team collaboration for all experiences you own.

Grants access to manage your experiences and certain information associated with your experiences (e.g. localization information).

Grants access to read your experiences' localization information.

Grants access to modify your experiences' localization preferences.

Grants access to manage your user account.

Grants access to modify user localization preferences.

Allows you to view the status, logs, and results of Luau execution tasks for the associated place.

Allows you to create new Luau execution tasks for the associated place.

Grants access to asynchronously flush all data structures in the universe.

Grants access to discard read items from the front of the queue.

Grants access to read items at the front of the queue.

Grants access to read your memory store items.

Grants access to create, update, and delete map items.

This grants the ability to publish messages on behalf of users.

This allows sending notifications from your experience to users.

(Deprecated) Grants access to read a list of entries in an ordered data store.

(Deprecated) Grants access to create a new entry in an ordered data store.

Grants access to list entries from an ordered data store.

Grants access to create entries in an ordered data store.

This allows listing secrets associated with your experience.

This allows creating and updating secrets associated with your experience.

This permission allows you to submit an evaluation job and view the job result.

Grants access to read about your subscription products.

This allows you to read thumbnail information on your behalf.

Grants the ability to read game analytics.

Grants the ability to read place information.

Grants the ability to edit place information.

Grants access to publish new versions of experiences to Roblox.

Grants the ability to read experience information.

Grants access to edit the authorized user's experiences.

Allows you to view user restrictions in the experience.

Allows you to edit user restrictions in the experience.

This allows viewing notifications sent to your account.

Grants the ability to read the authorized user's premium and verified status.

This allows you to view the authorized user's social accounts.

This enables Single Sign-On functionality.

This grants access to read your profile information.