in the FB API explorer try fetching likes for a post, i used 700182169998352
the "/700182169998352/likes" return:
{
"data": [
{
"id": "663945278",
"name": "Irene Olsson Wikler"
},
{
"id": "100002437916716",
"name": "Frida Braxell"
},
{
"id": "1135121633",
"name": "Rex Leopold Olsson"
}
],
"paging": {
"cursors": {
"after": "MTEzNTEyMTYzMw==",
"before": "NjYzOTQ1Mjc4"
}
}
}
the "/700182169998352/likes?summary=1" return:
{
"data": [
{
"id": "663945278",
"name": "Irene Olsson Wikler"
},
{
"id": "100002437916716",
"name": "Frida Braxell"
},
{
"id": "1135121633",
"name": "Rex Leopold Olsson"
}
],
"paging": {
"cursors": {
"after": "MTEzNTEyMTYzMw==",
"before": "NjYzOTQ1Mjc4"
}
},
"summary": {
"total_count": 3
}
}
so by adding the ?summary=1
you get an extra part in the json result named summary,
and containng the total_count, in my case 3