Until 2008 the assumed number of Sobibor victims had always been 250.000. Recent research, done by Jules Schelvis in collaboration with the German historian Peter Witte and the United States Holocaust Museum in Washington D.C. resulted in a lower number.

It has been established that 170.000 Jews from various European countries were murdered in Sobibor. The majority of these victims, an estimated 100.000, came from Poland. The additional victims came from The Netherlands (over 33.000), The Soviet Union, Germany, Czechoslovakia, France, Austria, and Yugoslavia. Please read the chapter Transporten en Aantallen (transports and numbers) in the book Vernietigingskamp Sobibor by Jules Schelvis (7th print) for a deeper analysis of the number of victims.