curl -X GET \
  -d 'ad_format="DESKTOP_FEED_STANDARD"' \
  -d 'access_token=<ACCESS_TOKEN>' \
https://graph.facebook.com/v26.0/<CREATIVE_ID>/previews

curl -X GET \
  -d 'creative="<CREATIVE_SPEC>"' \
  -d 'ad_format="<AD_FORMAT>"' \
  -d 'access_token=<ACCESS_TOKEN>' \
https://graph.facebook.com/v26.0/act_<AD_ACCOUNT_ID>/generatepreviews

https://graph.facebook.com/<API_VERSION>/<AD_ID>/previews

https://graph.facebook.com/<API_VERSION>/<AD_CREATIVE_ID>/previews

https://graph.facebook.com/<API_VERSION>/act_<AD_ACCOUNT_ID>/generatepreviews
https://graph.facebook.com/<API_VERSION>/generatepreviews

curl -G \
  --data-urlencode 'creative={
    "object_story_spec": {
      "link_data": {
        "call_to_action": {"type":"SIGN_UP","value":{"link":"<URL>"}},
        "description": "Description",
        "link": "<URL>",
        "message": "Message",
        "name": "Name"
      },
      "page_id": "<PAGE_ID>"
    }
  }' \
  -d 'ad_format=DESKTOP_FEED_STANDARD' \
  -d 'access_token=<ACCESS_TOKEN>' \
https://graph.facebook.com/v26.0/act_<AD_ACCOUNT_ID>/generatepreviews

curl -X GET \
  -d 'creative={
       "object_story_id": "<PAGE_ID>_<POST_ID>"
     }' \
  -d 'ad_format="DESKTOP_FEED_STANDARD"' \
  -d 'access_token=<ACCESS_TOKEN>' \
https://graph.facebook.com/v26.0/act_<AD_ACCOUNT_ID>/generatepreviews

curl -X GET \
  -d 'creative={
       "object_story_spec": {
         "link_data": {
           "call_to_action": {
             "type": "USE_APP",
             "value": {
               "link": "<URL>"
             }
           },
           "description": "Description",
           "link": "<URL>",
           "message": "Message",
           "name": "Name",
           "picture": "<IMAGE_URL>"
         },
         "page_id": "<PAGE_ID>"
       }
     }' \
  -d 'ad_format="MOBILE_FEED_STANDARD"' \
  -d 'access_token=<ACCESS_TOKEN>' \
https://graph.facebook.com/v26.0/act_<AD_ACCOUNT_ID>/generatepreviews

curl -X GET \
  -d 'ad_format="INSTAGRAM_EXPLORE_GRID_HOME"' \
  -d 'access_token=<ACCESS_TOKEN>' \
  https://graph.facebook.com/v26.0/<AD_ID>/previews

{
  "data": [
    {
      "body": "<iframe src=\"https://www.facebook.com/ads/api/preview_iframe.php?d=AQKuwYcWpyFgVKLORPWQi52_uTud4v8PpMoDtyBfntL65i0iFtgkiXWN5S4JMBhq-UMKQmvxXFexVxu-5l5Xbf4WWRP48sCAtn3ArQAXwbdrD5qH0EL2z34K-gAgYyENd80cOGAdhVreKGJZvPkLbjDS3iDkdqdNNJQ6yaAFTmUpaz__cjgmhVVCUW68wU3UOZwqlv376mkijYR57Sm2OlyES4U6ivMPNGDx4xnZEd5d8kWyagDD-lPbCaGEk0nnQF5mnyeV9pFqdByhq-IqN6n0ZhSWjCPXZQa84wu5GNQ70YR2w7QxEYoiWCgI2WP0Z2OPeUMiNOf9bhYB-TBZJZ7G6HylsOnzzII9FQ8-0K-b_Q&t=AQJws9t-TtIGrKoFtCM\" width=\"274\" height=\"213\" scrolling=\"yes\" style=\"border: none;\"></iframe>"
    }
  ]
}

curl -X GET \
  -d 'ad_format="INSTAGRAM_SEARCH_CHAIN"' \
  -d 'access_token=<ACCESS_TOKEN>' \
  https://graph.facebook.com/v26.0/<AD_ID>/previews

{
  "data": [
    {
      "body": "<iframe src=\"https://www.facebook.com/ads/api/preview_iframe.php?d=AQKVMPdwuorP3mliXRaOi0TCSvsGRfucEzBTnB4jghArle84f8kBjvJmX3gmdjniUjohKA3GUppDZqljStZwxxRRxkQl9Y4R1o5wV4zRGE3xO3NHf1_qBbFM_uEIGAnAvptMWo_DLpbiIqIYFMjxbXNELzmZQsR0gnbBjaXM9i6gkI29dnHPqnm4xGvPxo2w8RWeXfWvmik2C96_2PrhrRhh4NKL3SOmFC9JDVsTp9Z6SYDlLVcLJWwpRKmciAZqEMOnMEFgepVTZ39yJ4ZiAMRo76RK9XNVGcornsUBtxI8cZHKtdW7nmj3ivq09_NGGUnFiJdJaPm-Mk-obM3K0QyOvgHKwnmLn7wvMiizJeXPEWAcSBa4DPUFLAO1mSuaKla0VQ6tzAM4BqFU9LJOG1-zZmPec7wKxQGDcrXoCOKfv2xkLyzECc-oDS0JJgvxxlo&t=AQI8ECKvkemIoVDaDrs\" width=\"274\" height=\"213\" scrolling=\"yes\" style=\"border: none;\"></iframe>"
    }
  ],
  "__www_request_id__": "AzCC2RoeSL0rMbSPTYDyDHa"
}