As you know, Kick Tolerance is the maximum gas kick volume for required Kick Intensity at a certain depth that you are able to successfully shut-in and circulate gas kick out of a well without breaking down formation at shoe.
There are several factors affecting kick tolerance as listed below:
1. Leak Off Test (LOT) of casing shoe: More LOT you have, the more kick tolerance (KT) will be; therefore, the deeper TD can be drilled.
2. Hole TVD: The deeper of well TVD is, the less kick tolerance will be.
3. Mud weight: The heavier mud weight is, the more KT will be.
4. Formation pressure: If you have more formation pressure, you will have more kick intensity (kick intensity = formation pressure – current mud weight). Therefore, KT will be smaller.
5. Kick size: if you expect bigger size of kick, you must have more KT.
Practically, personnel should frequently update kick tolerance during drilling operation because several parameters change while drilling.
Ref book: 
Formulas and Calculations for Drilling, Production and Workover, Second Edition
Well Control Books
