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+[//]: # (title: rename)
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Modify-->
+
+Renames one or several columns without changing its location in [`DataFrame`](DataFrame.md).
+
+```kotlin
+df.rename { columns }.into(name)
+df.rename { columns }.into { nameExpression }
+
+nameExpression = (DataColumn) -> String
+```
+
+**Related operations**: [](moveRename.md)
+
+See [column selectors](ColumnSelectors.md) for how to select the columns for this operation.
+
+<!---FUN rename-->
+<tabs>
+<tab title="Properties">
+
+```kotlin
+df.rename { name }.into("fullName")
+```
+
+</tab>
+<tab title="Strings">
+
+```kotlin
+df.rename("name").into("fullName")
+```
+
+</tab></tabs>
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Modify.rename.html" width="100%"/>
+<!---END-->
+
+
+<!---FUN renameExpression-->
+<tabs>
+<tab title="Properties">
+
+```kotlin
+df.rename { age }.into {
+    val mean = it.data.mean()
+    "age [mean = $mean]"
+}
+```
+
+</tab>
+<tab title="Strings">
+
+```kotlin
+df.rename("age").into {
+    val mean = it.data.cast<Int>().mean()
+    "age [mean = $mean]"
+}
+```
+
+</tab></tabs>
+<inline-frame src="resources/org.jetbrains.kotlinx.dataframe.samples.api.Modify.renameExpression.html" width="100%"/>
+<!---END-->
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.RenameToCamelCase-->
+
+## renameToCamelCase
+
+A special case of `rename` that renames all column names in a DataFrame to "camelCase" format.
+
+This function standardizes column names by converting them from various naming styles—such as "snake_case",
+"PascalCase", "kebab-case", or "space delimited formats" into a consistent "camelCase" form.
+
+The transformation follows Kotlin naming conventions for variables and properties, making the resulting
+column names idiomatic and easier to use in Kotlin code, which is especially useful
+in [extension properties usage](extensionPropertiesApi.md).
+
+Use it right after loading raw data to normalize column names into a consistent format.
+This is especially helpful when preparing the data for further transformations, column access,
+or integration with Kotlin APIs—making the DataFrame easier and more predictable to work with.
+
+### Examples
+
+<!---FUN notebook_test_rename_3-->
+
+```kotlin
+df
+```
+
+<!---END-->
+
+<inline-frame src="./resources/notebook_test_rename_3.html" width="100%" height="500px"></inline-frame>
+
+Rename selected columns to "camelCase":
+
+<!---FUN notebook_test_rename_4-->
+
+```kotlin
+df.rename { ColumnA and `COLUMN-C` }.toCamelCase()
+```
+
+<!---END-->
+
+<inline-frame src="./resources/notebook_test_rename_4.html" width="100%" height="500px"></inline-frame>
+
+Rename all columns (including nested) to "camelCase":
+
+<!---FUN notebook_test_rename_5-->
+
+```kotlin
+df.renameToCamelCase()
+```
+
+<!---END-->
+
+<inline-frame src="./resources/notebook_test_rename_5.html" width="100%" height="500px"></inline-frame>
+
+### Transformation Rules and Examples
+
+* Delimiters (underscores, dashes, spaces, etc.) are removed.
+* The first word is kept lowercase; all subsequent words are capitalized.
+* An underscore is inserted between consecutive numbers to improve readability.
+* If a name contains no letters or digits, it remains unchanged.
+
+| Original                         | camelCase                    |
+|----------------------------------|------------------------------|
+| hello_world                      | helloWorld                   |
+| HelloWorld                       | helloWorld                   |
+| json.parser.Config               | jsonParserConfig             |
+| my.var_name test                 | myVarNameTest                |
+| thirdColumn                      | thirdColumn                  |
+| someHTMLParser                   | someHtmlParser               |
+| RESTApi                          | restApi                      |
+| OAuth2Token                      | oAuth2Token                  |
+| GraphQLQuery                     | graphQlQuery                 |
+| TCP_3_PROTOCOL                   | tcp3Protocol                 |
+| 123hello_world456                | 123HelloWorld456             |
+| API_Response_2023                | apiResponse2023              |
+| UPPER_case-LOWER                 | upperCaseLower               |
+| 12parse34CamelCase               | 12Parse34CamelCase           |
+| snake_case_example               | snakeCaseExample             |
+| dot.separated.words              | dotSeparatedWords            |
+| kebab-case-example               | kebabCaseExample             |
+| MIXED_Case_with_123Numbers       | mixedCaseWith123Numbers      |
+| ___!!!___                        | ___!!!___                    |
+| 1000.2000.3000                   | 1000_2000_3000               |
+| UPPERCASE                        | uppercase                    |
+| alreadyCamelCased                | alreadyCamelCased            |
+| justNumbers123                   | justNumbers123               |
+| Just_Special$Chars!!             | justSpecialChars             |
+| singleword                       | singleword                   |
+| word_with_underscores_and-dashes | wordWithUnderscoresAndDashes |
+| 10-20-aa                         | 10_20Aa                      |
+
+