Schedule Slippage Calculator
Use this free Schedule Slippage Calculator to determine whether your project is ahead or behind schedule. Enter the planned and actual durations to get your percentage of slippage.
Schedule Slippage Calculator
How Schedule Slippage Is Calculated
Schedule slippage (%) = ((Actual Duration − Planned Duration) ÷ Planned Duration) × 100
A positive result means the project took longer than planned (behind schedule). A negative result means it finished faster (ahead of schedule). Zero means actual duration matched the plan.
Example
If a project was planned for 60 days but took 66 days, slippage = ((66 − 60) ÷ 60) × 100 = 10% delay.
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