There is no fixed number of hours in Jain scriptures that says, “A Jain monk must sleep X hours.” But in practice, a few clear principles are followed:

1. Very little sleep, only as much as truly needed

- Monks aim for apramatta (constant awareness). - So they try to reduce sleep gradually, without harming health. - Many senior monks are known to sleep only a few hours, but this is a result of long practice, not a rule for everyone.

1. Simple way of sleeping

- They sleep on the floor or a simple wooden board, without mattress or pillow. - No comfort, no luxury – just enough rest so the body can continue spiritual effort.

1. No daytime sleeping (as far as possible)

- Sleeping during the day is generally avoided, as it increases laziness and reduces time for sādhanā (spiritual practice).

1. Night used for sādhana, not only for rest

- A lot of the night is spent in samayik, pratikraman, svādhyāy (scripture study), and dhyān (meditation). - Sleep is only a short break to support this spiritual routine.

1. Digambar / Shwetambar

- Both traditions follow the same spirit: minimum necessary sleep, maximum spiritual awareness. - Exact hours can differ from monk to monk according to health, age, and guidance of their Āchārya, not by sect.

So the best, authentic answer is: Jain monks try to sleep as little as possible, only enough to keep the body fit for spiritual practice. There is no fixed hour-count in the Agams; the emphasis is on alertness, non‑laziness, and simple, non-luxurious rest.