PMP Formulas Cheat Sheet: Every Formula You Need

Do You Really Need to Know Formulas for the PMP Exam?

Yes, but with an important caveat. The current PMP exam is not a math test. You will not face dozens of calculation questions. However, you can expect several questions that require formula knowledge — and these are essentially free points if you have prepared. Unlike situational questions where judgment is required, calculation questions have objectively correct answers. Know the formula, do the math, get the point.

This guide covers every formula that may appear on the PMP exam, organized by knowledge area. Bookmark this page and review it regularly during your preparation.

Earned Value Management (EVM) Formulas

EVM is the most formula-heavy topic on the exam. Master these in order:

Base Measurements

Planned Value (PV): The authorized budget for scheduled work at a given point in time
Earned Value (EV): The value of work actually completed, measured against the baseline
Actual Cost (AC): The total cost incurred for work performed
Budget at Completion (BAC): The total authorized budget for the project

Variance Formulas

Cost Variance (CV) = EV - AC — Positive means under budget
Schedule Variance (SV) = EV - PV — Positive means ahead of schedule

Performance Indices

Cost Performance Index (CPI) = EV / AC — Greater than 1.0 means under budget
Schedule Performance Index (SPI) = EV / PV — Greater than 1.0 means ahead of schedule

Memory trick: For variances, EV always comes first. For indices, EV is always the numerator.

Forecasting Formulas

Estimate at Completion (EAC) = BAC / CPI — Current cost performance continues
EAC = AC + (BAC - EV) — Remaining work at original rate
EAC = AC + [(BAC - EV) / (CPI x SPI)] — Both cost and schedule performance considered
Estimate to Complete (ETC) = EAC - AC — How much more will be spent
Variance at Completion (VAC) = BAC - EAC — Expected budget variance at the end

To-Complete Performance Index (TCPI)

TCPI (to meet BAC) = (BAC - EV) / (BAC - AC)
TCPI (to meet EAC) = (BAC - EV) / (EAC - AC)

TCPI greater than 1.0 means you need to perform better than planned on remaining work. Greater than 1.0 is harder to achieve.

Estimating Formulas

Three-Point Estimates

PERT (Beta Distribution): (O + 4M + P) / 6 — Weighted toward the most likely estimate
Triangular Distribution: (O + M + P) / 3 — Equal weight to all three estimates
Standard Deviation (sigma): (P - O) / 6
Variance: [(P - O) / 6]^2 — Standard deviation squared

Where O = optimistic, M = most likely, P = pessimistic.

Communication Formula

Communication Channels = n(n-1) / 2

Where n = number of people including the project manager. When a person is added, the number of new channels equals the old total of people.

Procurement Formulas

Point of Total Assumption (PTA)

Used with Fixed Price Incentive Fee contracts:

PTA = [(Ceiling Price - Target Price) / Buyer's Share Ratio] + Target Cost

The PTA is the cost point where the seller bears all additional cost overruns because the ceiling price has been effectively reached.

Schedule Formulas

Total Float = Late Start - Early Start (or Late Finish - Early Finish)
Free Float = Early Start of successor - Early Finish of current activity - 1

Study Strategy for Formulas

Create a formula sheet from memory before each practice exam. Repeat until you can write all formulas from recall in under five minutes. On exam day, use the first few minutes to write down your formulas on the scratch paper provided. This reduces anxiety and frees mental energy for the scenarios. For a printable version, visit our cheat sheets page, and practice formula-based questions on our exam simulator.