The formula and what goes in the denominator
Attendance percentage = (days present ÷ working days) × 100. The tricky part is defining both numbers. Working days are the days the employee was scheduled to work: calendar days minus weekly offs and paid holidays. For a six-day-week worker in a 30-day month with four Sundays and one holiday, working days are 25. For a 12-hour rotating guard on a 4-on-2-off pattern, working days follow the roster, not the calendar.
Days present includes full days and half days at 0.5. Whether approved paid leave counts as present depends on the purpose: for an attendance incentive most companies exclude leave days from both numerator and denominator (so leave neither helps nor hurts); for an absenteeism rate only unplanned absence counts. State the rule in the attendance policy so HR and payroll compute it the same way.
- Working days = calendar days − weekly offs − paid holidays (or roster days for shift staff)
- Present = full days + 0.5 × half days
- Approved leave: exclude from both sides for incentives; count as absent only for unplanned absence metrics
- Late marks that convert to a half day under policy reduce the present count
- Use one consistent rule per company, not per manager
Employee versus student usage
Schools and colleges compute attendance percentage on classes or days held, with a common 75% minimum to sit exams. Employers use the same arithmetic but tie it to money: an attendance bonus at 100% or above 96%, eligibility for a monthly incentive, or a threshold below which a warning is issued. A school register and a factory muster roll look similar but the employer's version also feeds the paid-day count for salary.
For workers, a second cousin of this metric is the paid-day count used in salary: paid days = present days + paid leave + weekly offs + holidays, out of 30 or 31. That is a payroll figure, not an attendance percentage, and mixing the two causes disputes. See how to calculate salary per day and LOP.
Common mistakes
Dividing by calendar days (30) instead of working days (26 or 25) makes everyone look 13–17% worse and breaks incentive thresholds. Counting a weekly off as absent for someone who was rostered off is the same error in another form. Ignoring half days, or treating a late mark as a full absence, inflates penalties in ways an employee can challenge. And for multi-site contract staff, computing the percentage against the wrong site's roster produces nonsense; the roster the person was actually assigned to is the only valid denominator.
September has 30 days. The associate has four weekly offs and one paid holiday, so working days = 25. She was present on 22 full days, took two half days (1.0) and one approved casual leave. For the attendance incentive, leave is excluded: present = 23.0 out of 24 = 95.8%. The store's incentive threshold is 96%, so she misses it by one half day. For the absenteeism report, unplanned absence = 0 days, because the leave was approved.
Attend Mitra's analytics dashboards report attendance percentage per employee, department, branch and site using the shift roster as the denominator, with half days counted as 0.5 and leave treated per your policy setting. The same records feed the paid-day count in attendance-linked payroll and can be exported to CSV or XLSX.