Project Budget Variance Calculator
Calculate budget variance, cost performance index, and estimate at completion for project cost control
About this calculator
The Project Budget Variance Calculator is an essential tool for project managers and financial controllers to monitor project cost performance and predict final budget outcomes. It calculates three critical metrics: budget variance (actual vs planned costs), cost performance index (efficiency ratio), and estimate at completion (projected total project cost). This calculator helps identify cost overruns early, enables proactive budget management, and supports informed decision-making for project financial control and resource allocation.
How to use
Enter your planned budget, actual costs spent to date, and percentage of work completed. The calculator will instantly compute your budget variance, showing whether you're over or under budget, the cost performance index indicating efficiency, and the estimated total project cost at completion based on current spending trends.
Frequently asked questions
What does a Cost Performance Index below 1.0 mean?
A CPI below 1.0 indicates you're spending more than planned for the work completed, meaning the project is over budget and cost-inefficient.
How is Estimate at Completion calculated?
EAC is calculated by dividing the total planned budget by the Cost Performance Index, projecting final costs based on current spending efficiency.
When should I use this calculator during my project?
Use this calculator regularly throughout project execution, ideally during monthly budget reviews or when significant project milestones are completed for accurate tracking.