Earned Value Calculator: Cost Variance, EAC and CPI

Earned Value Management (EVM) model to forecast project completion costs (EAC), cost performance index (CPI), and budget overruns.

Earned value (EVM): calculating CPI, SPI and the EAC final cost

Earned value management compares what has been produced (EV) with what has been spent (AC) and what was planned (PV). The cost performance index CPI = EV ÷ AC projects the final cost: EAC = original budget ÷ CPI. A €120,000 project that is 45% done after spending €72,000 has a CPI of 0.75 and will finish around €160,000 if performance does not change.

Formulas used

  • PV (planned value) = BAC × % progress planned to date; EV (earned value) = BAC × % actually completed.
  • CPI = EV ÷ AC; SPI = EV ÷ PV. An index below 1 signals a cost overrun or a delay.
  • EAC = BAC ÷ CPI: the rest of the project is assumed to run at the same efficiency as so far.
  • VAC = BAC − EAC (negative = expected overrun); ETC = EAC − AC (still to spend).

Example with the default values

BAC of €120,000, 60% progress planned, 45% achieved, €72,000 spent. PV = €72,000, EV = €54,000. Cost variance EV − AC = −€18,000 and schedule variance EV − PV = −€18,000. CPI = 54,000 ÷ 72,000 = 0.75: each euro spent produces only 75 cents of work. SPI = 0.75. EAC = 120,000 ÷ 0.75 = €160,000, an expected overrun (VAC) of €40,000 with €88,000 still to spend (ETC). To stay within the original budget, the remaining work would need an efficiency of (120,000 − 54,000) ÷ (120,000 − 72,000) = 1.38: that is the TCPI, which the tool calculates but does not display.

Limits

  • The EAC used is the "current pace" forecast. PMI describes other variants (remaining work at planned cost, CPI and SPI combined) that give a different amount.
  • Progress in % is entered by hand, so the result is only as good as that estimate.
  • If nothing has been spent yet, CPI is set to 1 by convention; if nothing has been completed, EAC stays equal to the budget.

Among the site's project tools, this one forecasts a project's final cost from its progress; the profitability calculator tracks the margin on billed work, and the working-days calculator sets dates.

Sources and dates: earned value definitions from the Project Management Institute (PMI): CPI, SPI, EAC = BAC ÷ CPI when future performance matches past performance, TCPI = (BAC − EV) ÷ (BAC − AC) (checked 14/10/2026).

Frequently Asked Questions

How do you calculate a project's EAC?

The most common formula is EAC = BAC ÷ CPI, where CPI = earned value ÷ actual cost. For a €120,000 budget and a CPI of 0.75, EAC is €160,000. It assumes the rest of the project runs at the same efficiency as so far.

What does a CPI of 0.8 mean?

Each euro spent has produced 80 cents of planned work: the project is costing 25% more than planned for what has been done. On a €100,000 budget, the EAC would be €125,000.

What is the difference between CPI and SPI?

CPI (EV ÷ AC) measures spending efficiency, SPI (EV ÷ PV) measures progress against the schedule. With 45% achieved against 60% planned, SPI is 0.75: the project has produced three quarters of what it should have by this date.

What is TCPI?

TCPI = (BAC − EV) ÷ (BAC − AC) gives the efficiency needed on the remaining work to meet the original budget. In the default example it is 1.38: you would have to produce €1.38 of work per euro spent, which is rarely realistic, so a re-baseline should be considered.

Is this tool really free?

Yes, all tools on Kristools are 100% free and accessible without registration.

Is my data protected?

Yes. All processing is performed directly and securely inside your browser. No personal data is sent to our servers.