If running the GUI version of Core, you MUST use the console to run gtblockchaininfo:
confused for a moment because of this then there was another explanation that you noted down helps me out
day 1
{
"chain": "main",
"blocks": 528275,
"headers": 901381,
"bestblockhash": "0000000000000000000002bbb13fb21095599b3e18f4de5cb8f1c84d02bbf84e",
"difficulty": 5077499034879.017,
"time": 1529445095,
"mediantime": 1529443439,
"verificationprogress": 0.2615033623449411,
"initialblockdownload": true,
"chainwork": "00000000000000000000000000000000000000000218a80c94e2086e2c963878",
"size_on_disk": 1896803477,
"pruned": true,
"pruneheight": 526187,
"automatic_pruning": true,
"prune_target_size": 4999610368,
"warnings": [
]
}