Spot gold is the over-the-counter London price for immediate settlement, traded by retail clients as XAUUSD with a 100-ounce standard contract and a 0.01-lot (one ounce) minimum and no expiry.
Gold futures are exchange-traded and centrally cleared: COMEX GC is 100 troy ounces and micro gold MGC is 10 troy ounces, each with a defined expiry month that must be closed or rolled.
Spot CFDs suit small accounts and precise intraday sizing, paying spread, commission and daily swap. Futures suit larger multi-day positions with transparent exchange fees and public volume. COMEX futures volume leads spot during the 13:00 to 17:00 UTC window.