Earned Value S-Curve Calculator

The three-curve earned value picture — planned value, earned value, actual cost — with the standard schedule and cost metrics. Enter each period's increment; the tool accumulates. Runs entirely offline; everything persists in this browser via localStorage.

Use limits: Earned value is only as honest as the percent-complete basis behind EV. Units in place × budgeted unit value beats anyone's gut percentage. This page implements the textbook formulas, including EAC = BAC / CPI — the most common forecast, but not the only one; your contract or PMO may mandate AC + bottom-up ETC or a composite index. Use the mandated method for the report of record.

Budget

Budget at completion (BAC, $)

Periods (enter each period's increment; leave EV/AC blank for future periods)

Period	PV	EV	AC	Σ PV	Σ EV	Σ AC

PV, EV, AC are per-period dollar amounts. The Σ columns are the running cumulative the curves and metrics use. The last period with an EV entry is the data date.

Earned value — cumulative through the data date

Data date (last period with EV)	—
Percent complete (EV / BAC)	—
Schedule variance SV = EV − PV	—
Cost variance CV = EV − AC	—
Schedule performance SPI = EV / PV	—
Cost performance CPI = EV / AC	—
Estimate at completion EAC = BAC / CPI	—
Estimate to complete ETC = EAC − AC	—
Variance at completion VAC = BAC − EAC	—

How the Numbers Are Derived

The metric chain

All variances and indices are cumulative at the data date — the last period with an EV entry. With cumulative PV, EV, AC: schedule variance SV = EV − PV and cost variance CV = EV − AC (positive is good). Indices are the ratio form: SPI = EV / PV, CPI = EV / AC. The forecast EAC = BAC / CPI assumes current cost performance continues to the end; ETC = EAC − AC is what's left to spend; VAC = BAC − EAC is the projected over/underrun. Percent complete is EV / BAC.

Reading SPI and CPI

Both are dimensionless: 1.00 is on plan, below is behind/over. This tool colors them — below 0.95 in the fail tone, 0.95–1.00 in the warn tone. SV in dollars can look alarming on a big job; the index normalizes it. Note SPI drifts back toward 1.0 near the end even on a late job, because PV catches up to EV as the plan runs out — which is why schedule is better judged on the actual dates than on a terminal SPI.

Field notes

The 90% syndrome — a job that reports 90% complete for months — is an EV basis problem, not a productivity problem. If EV came from quantities in place it would move; if it came from a gut percentage it stalls at 90 because nobody wants to claim the last 10 they can't back up.
CPI is remarkably stable after roughly 20% complete. A bad CPI early is a forecast of the final number, not a blip to explain away. Take the early signal seriously.
EAC = BAC / CPI is one formula. When schedule and cost are both hurting, EAC = AC + (BAC − EV) / (CPI × SPI) is harsher and sometimes contractually required. A bottom-up ETC re-estimate beats any index late in the job.
Earn value on the same basis you planned it. If PV was loaded by unit rates, earn EV by units installed — mixing bases makes SV meaningless.

References

PMI — The Standard for Earned Value Management.

AACE International — recommended practices on earned value and forecasting (e.g. 17R-97, EAC methods).