I know the profi plan has 40 gigas of bandwitdh transfer for month , but how the bandwidth is metered? is there a daily quota or limit , i dont want surprises

Bandwidth is metered on monthly basis.

Btw Profi package includes 50 Gb of bandwidth

thanks for your answer Alec.

Is Gb short for Giga-BIT or Giga-BYTE?
Normally the small b would indicate "bit", but it sort of does not make sence to state the bandwidth limit in bits, does it?

50 Giga-BYTEs