How many people died in one day at Auschwitz?

Answer 1

The capacity of the crematoria was somewhat over 5,000 a day, but some corpses were burnt in pits. The Holocaust Encyclopedia estimates 6,000 a day for some months in 1944.

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The capacity for gassing for each of the two main krematoria (II and III) was 6 000 per day (or more if they worked overnight, of IV and V it was up to 5 000 per day and at peak they re-opened the little red cottage to increase capacity.

The crematoria could not burn that many corpses (faults appeared in the chimneys of krematorium IV when they worked around the clock), they perfered to have an excess of corpses than to have people waiting to be gasses, at peak there were two great cremation pits behind krematorim V (at the end towards the little red cottage).

Answer 2

The two gas chambers in Bunker I could accommodate 800 people at one go. Bunker 2, which contained three gas chambers holding 1,200 people, began operations in the summer of 1942. That summer Himmler also gave Hoess permission to build a new complex with four killing centres, containing a total of six gas chambers and 14 ovens, for cremating up to 8,000 corpses a day.

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Those new gas chamber could deal with about 7 000 at a time and process three or four sets per day, ie. up to 28 000 at the height of the Hungarian action Bunker 2 was re-opened to deal with the numbers at at the height in June 1944 30 000 were killed in one day.

They had to build 'cremation pits' as that was too many bodies for the ovens to burn.