Eddy Merckx is considered the greatest cyclist of all-time, and few argue with that assessment. He was so strong and rode hard so often that his nickname was "The Cannibal". He had no weaknesses – he was the strongest time trialist and climber in the world, and could outsprint all but a few rivals. Although his list of major victories is impressive, it is almost more impressive when one considers the records he holds for victories in major races. At his retirement he had won the most titles, or equal most, in the Tour de France (5), Giro d'Italia (5), World Championship road race (3), Milano-Sanremo (7), Gent-Wevelgem (3), La Flèche Wallonne (3), and Liège-Bastogne-Liège (5), and in that list, only Merckx's five Tour de France wins has been surpassed, intially by Lance Armstrong, with seven, prior to his doping disqualifications. Merckx won 19 monument races, the five greatest one-day classics, a record, with second on that list Roger De Vlaeminck, far back with 11. He is one of only three riders, with De Vlaeminck and Rik Van Looy, to have won all five of the monuments. Merckx's seven victories at Milano-Sanremo is an absolute record for most victories at any major one-day classic.

Merckx was the first man (and since equalled only by Stephen Roche) to win the Tour de France, Giro d'Italia and World Professional Road Race in the same year (1974). Only he, Jacques Anquetil, Felice Gimondi, Bernard Hinault, and Alberto Contador have ever won all three of the grand tours – Tour de France, Giro d'Italia, and the Vuelta à España, but only Merckx won at the other major tour, the Tour de Suisse. At the 1969 Tour de France, Merckx performed the still unequalled feat of winning the yellow jersey (overall winner), green jersey (points winner), and polka-dot jersey (King of the Mountains), something that could not even be imagined today in the professional peloton. His 11 victories in the major tours is an all-time record and might have been greater. He rode the Tour de France only eight times, twice when past his prime, and in 1973, because he was so dominant, he was asked by Tour organizers not to race because they felt his dominance was ruining the Tour.

Merckx is credited with over 500 major professional wins during his career. His grand tour wins were as follows\: 1969-72, 1974 Tour de France; 1968, 1970, 1972-74 Giro d'Italia; 1973 Vuelta à España; and the 1974 Tour de Suisse. He also won the following other jerseys in grand tours\: mountain classification – 1969-70 Tour de France; 1968 Giro d'Italia; points classification – 1969, 1971-72 Tour de France; 1968, 1973 Giro d'Italia; and the 1973 Vuelta à España. Merckx's three victories in the World Professional Road Race came in 1967, 1971, 1974, but he also won the World Amateur Championship on the road in 1964. In 1972, he set the World Hour Record, recording 49.431 km (30.722 miles) in Mexico City. That mark was broken in 1984 by Francesco Moser, but by then new bike technology had taken over, and subsequent hour marks were often due to improved bike design as much as the riders' abilities. The UCI eventually reverted to a "standard" bike classification, and with that new classification, Merckx's hour record was not bettered until 2000, and then by Chris Boardman riding only 10 metres further.

In other lesser tours and one-day classics, Merckx's victories can be summarized as follows\: Milano-Sanremo – 1966-67, 1969, 1971-72, 1975-76; La Flèche Wallonne – 1967, 1970, 1972; Gent-Wevelgem – 1967, 1970, 1973; Paris-Roubaix – 1968, 1970, 1973; Liège-Bastogne-Liège – 1969, 1971-73, 1975; Ronde van Vlaanderen – 1969, 1975; Paris-Nice – 1969-71; Dauphiné-Libéré – 1971; Midi-Libre – 1971; Het Volk – 1971, 1973; Giro di Lombardia – 1971-72; Paris-Brussels – 1973; Grand Prix des Nations – 1973; Amstel Gold Race – 1973, 1975.

Merckx was not without his detractors. He was criticized by other riders because he never let up, always riding to win, often not giving lesser riders a chance to shine a bit. And he tested positive for drugs three times, in an era in which the doping penalties were less stringent. In retirement, though, he remains the all-time Belgian sporting legend, being voted Belgium's Sportsman of the 20th Century, and he was made a Baron by Albert II, King of Belgium in 1996. Merckx's son, Axel, later became a professional cyclist, though not with the success of his father, although he did win a bronze medal in the Olympic road race in 2004.