Launch vehicles are classed by NASA according to low Earth orbit payload capability:
Small-lift launch vehicle: < 2,000 kilograms (4,400 lb) - e.g. Vega
Medium-lift launch vehicle: 2,000 to 20,000 kilograms (4,400 to 44,100 lb) - e.g. Soyuz ST
Heavy-lift launch vehicle: > 20,000 to 50,000 kilograms (44,000 to 110,000 lb) - e.g. Ariane 5
Super-heavy lift vehicle: > 50,000 kilograms (110,000 lb) - e.g. Saturn V