---
name: "CURLOPT_SSLCERTTYPE"
section: "3"
platform: "macos"
package: "curl"
version: "166.0.0.0.1"
release: "macOS 26.5"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLOPT_SSLCERTTYPE"
---

# CURLOPT\_SSLCERTTYPE(3)

type of client SSL certificate

## NAME

CURLOPT\_SSLCERTTYPE - type of client SSL certificate

## SYNOPSIS

```
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLCERTTYPE, char *type);
```

## DESCRIPTION

Pass a pointer to a null-terminated string as parameter. The string should be the format of your certificate.

Supported formats are "PEM" and "DER", except with Secure Transport or Schannel. OpenSSL (versions 0.9.3 and later), Secure Transport (on iOS 5 or later, or OS X 10.7 or later) and Schannel support "P12" for PKCS#12-encoded files.

The application does not have to keep the string around after setting this option.

## DEFAULT

"PEM"

## PROTOCOLS

All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    curl_easy_setopt(curl, CURLOPT_SSLCERT, "client.pem");
    curl_easy_setopt(curl, CURLOPT_SSLCERTTYPE, "PEM");
    curl_easy_setopt(curl, CURLOPT_SSLKEY, "key.pem");
    curl_easy_setopt(curl, CURLOPT_KEYPASSWD, "s3cret");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
```

## AVAILABILITY

If built TLS enabled. Added in 7.9.3

## RETURN VALUE

Returns CURLE\_OK if TLS is supported, CURLE\_UNKNOWN\_OPTION if not, or CURLE\_OUT\_OF\_MEMORY if there was insufficient heap space.

## SEE ALSO

[**CURLOPT\_SSLCERT**(3)](/CURLOPT_SSLCERT/3.md), [**CURLOPT\_SSLKEY**(3)](/CURLOPT_SSLKEY/3.md)