---
description: "Learn more about: Data Alignment"
title: "Data Alignment"
ms.date: "11/04/2016"
f1_keywords: ["data.alignment"]
helpviewer_keywords: ["data alignment [C++]"]
ms.assetid: 35ac3d2d-a4b3-421b-954f-b7372b1f18e1
---
# Data alignment

The following C run-time functions support data alignment.

## Data-alignment routines

| Routine | Use |
|---|---|
| [`_aligned_free`](./reference/aligned-free.md) | Frees a block of memory that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md)or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md). |
| [`_aligned_free_dbg`](./reference/aligned-free-dbg.md) | Frees a block of memory that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) (debug only). |
| [`_aligned_malloc`](./reference/aligned-malloc.md) | Allocates memory on a specified alignment boundary. |
| [`_aligned_malloc_dbg`](./reference/aligned-malloc-dbg.md) | Allocates memory on a specified alignment boundary with extra space for a debugging header and overwrite buffers (debug version only). |
| [`_aligned_msize`](./reference/aligned-msize.md) | Returns the size of a memory block allocated in the heap. |
| [`_aligned_msize_dbg`](./reference/aligned-msize-dbg.md) | Returns the size of a memory block allocated in the heap (debug version only). |
| [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) | Allocates memory on a specified alignment boundary. |
| [`_aligned_offset_malloc_dbg`](./reference/aligned-offset-malloc-dbg.md) | Allocates memory on a specified alignment boundary (debug version only). |
| [`_aligned_offset_realloc`](./reference/aligned-offset-realloc.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md). |
| [`_aligned_offset_realloc_dbg`](./reference/aligned-offset-realloc-dbg.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) (debug version only). |
| [`_aligned_offset_recalloc`](./reference/aligned-offset-recalloc.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) and initializes the memory to 0. |
| [`_aligned_offset_recalloc_dbg`](./reference/aligned-offset-recalloc-dbg.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) and initializes the memory to 0 (debug version only). |
| [`_aligned_realloc`](./reference/aligned-realloc.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md). |
| [`_aligned_realloc_dbg`](./reference/aligned-realloc-dbg.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) (debug version only). |
| [`_aligned_recalloc`](./reference/aligned-recalloc.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) and initializes the memory to 0. |
| [`_aligned_recalloc_dbg`](./reference/aligned-recalloc-dbg.md) | Changes the size of a memory block that was allocated with [`_aligned_malloc`](./reference/aligned-malloc.md) or [`_aligned_offset_malloc`](./reference/aligned-offset-malloc.md) and initializes the memory to 0 (debug version only). |

## See also

[Universal C runtime routines by category](./run-time-routines-by-category.md)