It's ~25 dB (SPL) from 1m away, depending on how loudly one whispers, I suppose. ~50 dB at 1m is the level of speech, and ~10 dB at 1m is the level of just regular breathing. The magnitude of sound decays with distance, so distance from the source needs to be considered.
0 decibels SPL is about 10^-12 watts per square meter. 120 decibels SPL is about 1 watt per square meter. As indicated above, it is a logarithmic scale; every 10 decibels is a factor of 10 in watts/ square meter.