Teachers & educators
Attendance percentage calculator.
Attendance rate, absence rate, and the chronic absence line for a student.
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How do you calculate attendance percentage?
Attendance rate = days present ÷ days enrolled × 100, where days present = days enrolled − days absent. Attendance Works describes California's definition of a chronic absentee as a student absent on 10% or more of the school days in the year, counting excused and unexcused absences and suspensions, over the days the student is enrolled and school is in session. The number of absences that reaches the line is the enrolled days times the percentage, rounded up. This tool uses whole days and does not handle part-day absences.
Worked example. Out of 180 enrolled days, the 10% line is 18 absences. A student with 17 absences is at 90.6% attendance and one more absence reaches the line.
Frequently asked questions
How do I calculate attendance percentage?
Subtract days absent from days enrolled, divide by days enrolled and multiply by 100.
What is chronic absenteeism?
In California law as described by Attendance Works, it is missing 10% or more of the school days a student is enrolled, for any reason. Other states and districts set their own definitions, so change the line above if yours differs.
Does 90% attendance mean chronic absence?
A 90% attendance rate is an absence rate of 10%, which is at the line, so yes under a 10% definition.
Why use days enrolled and not the whole school year?
A student who joins mid-year is measured over the days they were enrolled and school was in session.
Sources
Checked
The 10% line is the California definition cited by Attendance Works; other jurisdictions differ and you can change it. Runs entirely in your browser. Nothing you type is sent or stored.
Scope
Attendance rules and definitions vary by district. For information and planning only. Not an official attendance record.