The salient features of the safe period calculator:

• By giving last period start date,shortest period cycle,longest period cycle you can know the safe period and unsafe period
• Safe period calculator shows the safe and unsafe days in green and red colours respectively
• Determine your fertile period in the ovulation cycle
• Identify your infertile period in the ovulation calendar
• Use the infertile days to enjoy unprotected intercourse
• Use the calculator in your own web page or blog. It is customizable in size and absolutely free of cost