How to Implement Pagination in ASP.NET Core Web API?

👉 Key logic:

• Skip = (PageNumber - 1) * PageSize

• Take = PageSize

Step 4: Update Controller

[HttpGet]
public async Task<IActionResult> GetProducts([FromQuery] PaginationParams paginationParams)
{
    var products = await _productService.GetProductsAsync(paginationParams);
    return Ok(products);
}

👉 Now API supports query parameters like:

/api/products?pageNumber=1&pageSize=10

Returning Pagination Metadata

It’s a good practice to send pagination details along with data.

Create Response Wrapper

public class PagedResponse<T>
{
    public IEnumerable<T> Data { get; set; }
    public int TotalRecords { get; set; }
    public int PageNumber { get; set; }
    public int PageSize { get; set; }
}

Update Service

public async Task<PagedResponse<Product>> GetProductsAsync(PaginationParams paginationParams)
{
    paginationParams.Validate();

    var query = _context.Products.AsQueryable();

    var totalRecords = await query.CountAsync();

    var data = await query
        .Skip((paginationParams.PageNumber - 1) * paginationParams.PageSize)
        .Take(paginationParams.PageSize)
        .ToListAsync();

    return new PagedResponse<Product>
    {
        Data = data,
        TotalRecords = totalRecords,
        PageNumber = paginationParams.PageNumber,
        PageSize = paginationParams.PageSize
    };
}

Controller Response

return Ok(await _productService.GetProductsAsync(paginationParams));

👉 Now response includes:

• Total records

• Current page

• Page size

Advanced Pagination with Filtering and Sorting

Pagination is often used with filtering and sorting.

Example:

public async Task<IEnumerable<Product>> GetProductsAsync(string search, string sortBy, PaginationParams paginationParams)
{
    var query = _context.Products.AsQueryable();

    if (!string.IsNullOrEmpty(search))
    {
        query = query.Where(p => p.Name.Contains(search));
    }

    if (!string.IsNullOrEmpty(sortBy))
    {
        query = sortBy.ToLower() switch
        {
            "price" => query.OrderBy(p => p.Price),
            _ => query.OrderBy(p => p.Name)
        };
    }

    return await query
        .Skip((paginationParams.PageNumber - 1) * paginationParams.PageSize)
        .Take(paginationParams.PageSize)
        .ToListAsync();
}

👉 This makes your API powerful and flexible.

Best Practices for Pagination in ASP.NET Core

1. Always Set Maximum Page Size

Prevents heavy queries that can crash your API.

2. Use Async Methods

Improves performance and scalability.

3. Return Metadata

Helps frontend understand total pages.

4. Use Indexing in Database

Improves query performance.

5. Consider Cursor Pagination for Large Data

Better for real-time systems like feeds.

Common Mistakes to Avoid

• ❌ Returning all data without pagination

• ❌ Not validating PageSize

• ❌ Ignoring total count

• ❌ Using large page sizes

Real-World Example Use Case

Imagine an e-commerce application:

• Products list → paginated

• Orders history → paginated

• Search results → paginated

Without pagination, your API will become slow and inefficient.

Summary

Pagination in ASP.NET Core Web API is a must-have feature for building scalable and high-performance applications. By using techniques like Skip and Take, along with proper validation and metadata, you can create APIs that are fast, efficient, and user-friendly. Implementing pagination not only improves backend performance but also enhances the overall user experience by delivering data in a structured and manageable way.