Send multipart form-data with cURL in PowerShell

Paste a curl command that sends multipart form-data and get idiomatic PowerShell code. We pick the right serialization for Invoke-RestMethod and set the correct Content-Type.

Quick answer

To convert a cURL command to PowerShell, paste it into the Toolpaper workbench below. It parses the command in your browser and emits idiomatic PowerShell code — headers, query string, request body, authentication (Bearer, Basic, API key), and cookies are all wired up automatically. No data is uploaded; conversion is fully client-side.

Prefer a different target? See the full cURL to PowerShell reference, or jump to the same guide in JavaScript, Node.js, or Python.

InputcURL command
MethodPOST·Headers0·Body—·Form2 fields· Chars 100
OutputShell · Invoke-RestMethod(PowerShell 7+)
$form = @{
  "file" = Get-Item "/path/to/photo.png";
  "caption" = "Hello"
}

$response = Invoke-RestMethod `
  -Uri "https://api.example.com/upload" `
  -Method "POST" `
  -Form $form `
  -MaximumRedirection 0
$response | ConvertTo-Json -Depth 10
Inspect

Example

A representative curl command for this scenario. Paste your own above to convert an exact match.

curl input
curl -X POST https://api.example.com/upload \
  -F "file=@/path/to/photo.png" \
  -F "caption=Hello"

Implementation notes

  • Content-Type is detected from -H headers first, then inferred from the body shape when the header is missing.
  • Each -F flag becomes a distinct part; file@ paths are surfaced as Invoke-RestMethod file handles so the multipart boundary stays valid.
  • Charset directives on Content-Type (e.g. application/json; charset=utf-8) survive the round trip.

Common mistakes

  • Setting Content-Type manually and then also using Invoke-RestMethod's helper — you end up with duplicate headers or the wrong one wins.
  • Forgetting @ in -F "file=@upload.png" — without it curl sends the literal string, not the file. The generator flags this.
  • Trusting the browser DevTools "Copy as cURL" to preserve charset — it often drops it. Clean panel restores common defaults.

Common questions

How is multipart form-data encoded in the generated PowerShell?
-F flags translate to multipart form-data with proper boundary handling — files={...} in Python, MultipartFormDataContent in C#, MultipartBody.Part in Java/Kotlin.
Does it preserve Content-Type?
Yes. The Content-Type header is honored and matched against the body so serialization stays consistent.
Is anything uploaded?
No. Parsing and generation happen entirely in your browser.

More payload types in PowerShell

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