curl to C#

Convert curl commands to C# HttpClient code for .NET 6+.

Load Preset Sample:

curl Command

C# Output

curl to C# HttpClient Converter

This tool converts curl commands into C# code using HttpClient — the standard .NET HTTP client available in .NET 6 and later. The generated code uses HttpRequestMessage for full control over headers and request bodies, and StringContent for JSON payloads. Basic auth via -u user:pass is converted to an AuthenticationHeaderValue. Supports common curl flags: -X, -H, -d, -u, and -k.

Built and maintained by Meet Shah · Last updated 4 August 2026

What this tool is used for

Converting an API's curl example into HttpClient code for .NET.
Reproducing a captured request inside an existing C# client.
Getting the content and header setup right for a POST.
Producing a snippet for a console tool or a minimal API handler.
Checking how auth headers attach to a request rather than a client.

Frequently Asked Questions

Why should I not wrap HttpClient in a using block?: Disposing HttpClient per request leaves sockets in TIME_WAIT and exhausts the connection pool under load — the well-documented socket exhaustion problem. Use a single static instance, or register IHttpClientFactory and inject typed clients.
What is the default timeout?: 100 seconds, set on the HttpClient instance rather than per request. For finer control pass a CancellationToken to SendAsync. Note the timeout applies to the whole operation including reading the body, not just the connect.
How do I send a JSON body?: new StringContent(json, Encoding.UTF8, "application/json"), or in .NET 5+ the simpler PostAsJsonAsync extension from System.Net.Http.Json, which serialises and sets the content type in one call.
Does HttpClient throw on a 404?: Not by default — inspect response.IsSuccessStatusCode, or call response.EnsureSuccessStatusCode() to convert a non-2xx into an HttpRequestException. Silently ignoring the status is a frequent porting bug.
How does curl's -k translate?: Supply an HttpClientHandler with ServerCertificateCustomValidationCallback set to return true. Scope it to a dedicated client — applying it globally disables certificate validation for every call your app makes.
Why does a long-lived HttpClient miss DNS changes?: Because it keeps connections open indefinitely and never re-resolves. Setting `PooledConnectionLifetime` on a `SocketsHttpHandler` recycles them on a schedule, which is the fix for a client that keeps talking to a decommissioned IP.
What does IHttpClientFactory solve?: It manages handler lifetime for you, avoiding both socket exhaustion from per-request clients and the stale-DNS problem from a static one. In an ASP.NET Core app it is the recommended way to get a client.
Should I use System.Text.Json or Newtonsoft?: System.Text.Json is built in, faster and the default for new code; Newtonsoft is more permissive and still needed for some features. The generated code targets the built-in one, which is stricter about case and trailing commas.

Common errors and gotchas

Creating and disposing an HttpClient per request, which exhausts sockets — reuse one or use the factory.
Setting a content-type on the client's default headers rather than on the content, which throws.
Calling `.Result` on an async call, which deadlocks in some contexts.
Assuming a non-2xx throws, when you must call `EnsureSuccessStatusCode` yourself.
Omitting a timeout, since the default of 100 seconds is often far too long.