PMP formula desk

Exam-ready formulas

Review EVM, PERT, finance, risk and contract calculations with a fast, filterable decision-oriented layout.

Exam cues

A ratio > 1 is usually favorable for CPI, SPI and BCR.

A positive variance is good for SV, CV and VAC; a negative variance signals delay or overrun.

Every PMP formula you need, with its meaning, plus a dictionary of abbreviations.

AbAbbreviations dictionary

Formulas

5 formulas

Earned Value
EV = BAC × % complete
The budgeted value of the work actually done — the pivot of all EVM. It's "how much budget you have earned".
Schedule Variance
SV = EV − PV
Ahead or behind, expressed in money: have we earned as much value as planned by now?
Positive = ahead; negative = behind.
Cost Variance
CV = EV − AC
Over- or under-cost in money: does the value earned cover what we spent?
Positive = under budget; negative = over.
Schedule Performance Index
SPI = EV / PV
Schedule efficiency as a ratio: 0.90 means progressing at 90% of the planned pace.
< 1 = behind; > 1 = ahead.
Cost Performance Index
CPI = EV / AC
Cost efficiency: 0.90 means you get $0.90 of value for every dollar spent.
< 1 = over budget; > 1 = under budget.

Formulas

7 formulas

EAC (current rate)
EAC = BAC / CPI
The forecast total cost if the current cost performance (CPI) continues. The default exam formula.
EAC (one-off variance)
EAC = AC + (BAC − EV)
Final cost if the past variance was a one-off and the rest runs at the planned budget.
EAC (cost and schedule)
EAC = AC + (BAC − EV) / (CPI × SPI)
Final cost when both cost AND schedule will keep weighing on the remaining work.
Estimate to Complete
ETC = EAC − AC
What remains to spend to finish (forecast final cost − already spent).
Variance at Completion
VAC = BAC − EAC
The forecast final budget variance: will we end over or under the original budget?
Negative = forecast overrun.
TCPI (to BAC)
TCPI = (BAC − EV) / (BAC − AC)
The efficiency you must hold on the REMAINING work to finish within the original budget.
> 1 = must outperform the past (hard).
TCPI (to EAC)
TCPI = (BAC − EV) / (EAC − AC)
Same idea, but to hold the REVISED budget (EAC) instead of the original.

Formulas

5 formulas

PERT (beta)
tE = (O + 4M + P) / 6
Expected duration (or cost) that heavily weights the most likely scenario (×4) to reduce bias.
The ×4 always goes on M.
Triangular
tE = (O + M + P) / 3
Simple average of the three scenarios, unweighted.
Standard deviation
σ = (P − O) / 6
The estimate's uncertainty: ±1σ covers ≈ 68% of cases, ±3σ ≈ 99.7%.
Uses only the extremes O and P.
Variance
σ² = ((P − O) / 6)²
The square of the standard deviation; variances add up along a path to estimate total uncertainty.
Total Float
Float = LS − ES = LF − EF
How long an activity can slip without delaying the project end.
Zero on the critical path.

Formulas

2 formulas

Communication channels
n (n − 1) / 2
The number of possible communication links; it grows with the square of the number of people (hence the complexity).
n = stakeholders (including yourself).
Expected Monetary Value
EMV = Probability × Impact
A risk's average expected value; sum the EMVs to size the contingency reserve.
Threat = negative; opportunity = positive.

Formulas

5 formulas

Present Value
PV = FV / (1 + r)^n
What a future amount is worth TODAY: future money is worth less (you discount it).
Net Present Value (NPV)
NPV = Σ discounted cash flows − Investment
The project's net value creation. NPV > 0 = worthwhile; among projects, pick the highest NPV.
Return on Investment
ROI = (Net benefit / Cost) × 100
Profitability as a percentage of the cost invested; prefer the highest ROI.
Benefit-Cost Ratio
BCR = Benefits / Costs
How much benefit per unit of cost; BCR > 1 = the project returns more than it costs.
Highest is preferred.
Payback period
Payback = Investment / annual cash flow
The time to recover the initial investment; prefer the shortest payback.

Formulas

2 formulas

Point of Total Assumption
PTA = ((Ceiling − Target) / buyer share) + Target cost
On an FPIF contract, the cost beyond which the SELLER bears 100% of the overrun (the buyer pays no more).
Margin (net value)
Profit = Value − Cost
The net value created: what the project returns once costs are subtracted.