---
title: "What is the difference between \"ToList()\" and \"ToArray()\" when materializing LINQ queries?"  
description: "What is the difference between \"ToList()\" and \"ToArray()\" when materializing LINQ queries?"  
author: "Steilla Mitchel"  
published: 2023-09-12  
updated: 2023-09-25  
canonical: https://www.mindstick.com/forum/159876/what-is-the-difference-between-tolist-and-toarray-when-materializing-linq-queries  
category: "c#"  
tags: ["c#", "linq"]  
reading_time: 3 minutes  

---

# What is the difference between "ToList()" and "ToArray()" when materializing LINQ queries?

What is the [difference](https://www.mindstick.com/articles/157114/good-news-or-bad-news-and-the-difference-is) between "ToList()" and "ToArray()" when materializing [LINQ](https://www.mindstick.com/articles/12007/language-integrated-query-linq-queries) [queries](https://www.mindstick.com/forum/33678/sub-queries-in-sql-server)?

## Replies

### Reply by Aryan Kumar

**ToList()** and **ToArray()** are methods in LINQ that are used to materialize (convert) the results of a LINQ query into different collection types: **List<T>** and **T[]** (array), respectively. While they serve a similar purpose, there are some key differences between the two:

**Return Type**:

- **ToList()**: It returns a **List<T>** that contains the results of the query.
- **ToArray()**: It returns an array (**T[]**) that contains the results of the query.

**Type Flexibility**:

- **ToList()** returns a **List<T>**, which is a dynamic, resizable collection. You can add or remove items from it, and it's well-suited for scenarios where you need to work with a collection that can grow or shrink.
- **ToArray()** returns a fixed-size array (**T[]**). Once the array is created, you cannot change its size. It's suitable when you need an immutable, fixed-size collection.

**Performance**:

- **ToList()** can be more efficient than **ToArray()** in cases where the final size of the collection is not known in advance because it doesn't require resizing operations like an array.
- **ToArray()** can be more efficient in scenarios where you know the exact size of the collection in advance because it avoids the overhead of resizing.

**API and Methods**:

- **List<T>** provides a richer set of methods and properties compared to arrays. For example, you can use **Add()**, **Remove()**, **Find()**, and more on a **List<T>**.
- Arrays (**T[]**) have a fixed size, and their methods are limited to basic operations like indexing and enumeration.

**Memory Consumption**:

- **ToList()** may consume slightly more memory than **ToArray()** because it has the flexibility to grow dynamically.
- **ToArray()** usually consumes less memory because it preallocates the exact amount of memory required for the elements.

**Use Cases**:

- Use **ToList()** when you need a dynamic, resizable collection and plan to modify or extend the collection.
- Use **ToArray()** when you need an immutable, fixed-size collection, or when you know the final size of the collection in advance.

Here's an example of using both methods:

```plaintext
var numbers = Enumerable.Range(1, 5);
// Using ToList()
var list = numbers.ToList(); // Returns List<int>
// Using ToArray()
var array = numbers.ToArray(); // Returns int[]
```

In summary, the choice between **ToList()** and **ToArray()** depends on your specific requirements and how you intend to use the result of the LINQ query. If you need a dynamic, resizable collection, use **ToList()**. If you need an immutable, fixed-size collection or want to minimize memory usage, use **ToArray()**.


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Original Source: https://www.mindstick.com/forum/159876/what-is-the-difference-between-tolist-and-toarray-when-materializing-linq-queries

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