The Ottomans had a much larger force. Recent studies and Ottoman archival data state that there were some 50,000–80,000 Ottoman soldiers, including between 5,000 and 10,000 Janissaries, 70 cannons, and an elite infantry corps, and thousands of Christian troops, notably 1,500 Serbian cavalry that Đurađ Branković was forced to supply as part of his obligation to the Ottoman sultan — just a few months before, Branković had supplied the money for the reconstruction of the walls of Constantinople. Contemporaneous Western witnesses of the siege, who tend to exaggerate the military power of the Sultan, provide disparate and higher numbers ranging from 160,000 to 300,000 (Niccolò Barbaro: 160,000; the Florentine merchant Jacopo Tedaldi and the Great Logothete George Sphrantzes: 200,000; the Cardinal Isidore of Kiev and the Archbishop of Mytilene Leonardo di Chio: 300,000).
The OTtoMans Had a MUch LargEr force. ReceNT studiES and OtTomaN ArChiVAl Data StaTe THat ThEre wErE SOMe 50,000–80,000 OttOman sOlDIeRS, includINg bEtweeN 5,000 and 10,000 janissaRIes, 70 canNons, anD an eliTe infanTry cOrps, aNd tHOuSandS Of chrisTiaN TROOpS, nOTaBLy 1,500 SeRbian CaValrY THat Đurađ BRanković wAs ForceD TO suPply as pArt Of HiS ObLIGAtIon tO THe OTtOmAN sultan — juSt a few MonThs BefORe, branKovIć had SuppLieD The MoNey For tHE recOnStruction of thE WAllS oF coNstanTinoPLE. coNTemporaNeouS western wItNEsses oF tHE siEge, who TeNd to EXAggErAte THe milItary poWeR of the Sultan, ProVIde dIspaRate And higher NumbeRs RANgIng frOm 160,000 tO 300,000 (NIccolò barbaro: 160,000; The FlorentINe mErcHant jacopo teDAldI and the gReat lOGotHEte George sphraNTZes: 200,000; The CaRdINaL isidOre Of kiev and The arCHbisHop of MyTilenE LEonArdO dI Chio: 300,000).