Free project forecast tool

Project Cost-Overrun Calculator

Forecast final project cost from current spending and actual progress, then see the likely overrun, remaining cash requirement and efficiency needed to recover the budget.

Simple calculator

Enter current project status

Physical-progress forecast

Budget & spending

Original project budget

Spent to date

Physical progress complete

Use actual work completed, not simply elapsed time.

Optional budget buffer

Remaining contingency / extra approved funding

Shown separately from the original budget.

Simple forecastImplied final cost = spending to date ÷ physical progress. This assumes the cost efficiency experienced so far continues through completion. If the project is at 0% progress, an implied final cost cannot be calculated.

Advanced calculator

Build an earned-value style cost forecast

Multiple EAC scenarios

Project status

Baseline budget (BAC)

Actual cost to date (AC)

Physical progress complete

Planned schedule progress

Remaining-cost assumptions

Committed but unspent cost

Acts as a floor on remaining forecast cost. Expected future cost efficiency

CPI

1.00 = remaining work performs exactly to budget. Remaining contingency / extra funding

Analysis discount rate

Used only for the optional present-value view.

Timing

Elapsed project months

months

Planned total project months

months

Target maximum final cost

Primary advanced forecastThe main forecast values remaining budgeted work using your expected future CPI, then applies committed-but-unspent costs as a floor. Separate scenario rows show current-performance EAC, planned-remaining EAC and a cost-and-schedule blended EAC.

EAC comparison

Four ways to forecast final project cost

Different assumptions, same project status

Forecast method	Final cost (EAC)	Remaining cost (ETC)	Overrun / underrun	Overrun %	Funding gap after contingency

Progress sensitivity

Final-cost forecast if physical progress is misestimated

Actual spend held constant

Physical progress	Implied CPI	Current-performance EAC	Primary EAC	Primary overrun	Funding gap

Future-efficiency sensitivity

Final cost at different remaining-work CPI levels

Commitment floor remains active

Future CPI	Primary EAC	Remaining spend	Overrun / underrun	Funding gap	Target gap / surplus

Contingency sensitivity

How much reserve would cover the forecast?

Final-cost forecast held constant

Contingency / extra funding	Total available funding	Forecast final cost	Funding gap / surplus	Reserve coverage

Scope

Progress quality determines forecast quality

This calculator is a planning model. Physical progress should represent work actually completed, not invoices paid or time elapsed. Earned-value style metrics can be misleading when scope has changed, work packages are uneven, progress estimates are subjective, commitments are incomplete, or major risks have not yet crystallized. The commitment-aware forecast uses committed-but-unspent cost as a floor on remaining spend, but it does not automatically model claims, change orders, financing cost, taxes, currency movements or probabilistic risk ranges.