What is Cost Variance (CV) in project management?

Cost Variance (CV) = Earned Value (EV) minus Actual Cost (AC). A positive CV means you have spent less than planned for the work done (under budget). A negative CV means you have overspent relative to the work completed (over budget).

What does a CPI less than 1.0 mean?

A Cost Performance Index (CPI) below 1.0 means you are getting less than $1 of work for every $1 spent — the project is over budget. CPI above 1.0 means you are getting more than $1 of value per $1 spent — the project is under budget.

How is Earned Value (EV) different from Actual Cost (AC)?

Earned Value (EV) is the budgeted value of work that has actually been completed — it measures progress in monetary terms. Actual Cost (AC) is the real money spent to date. They differ when spending is faster or slower than planned progress.

What is a good CPI for a project?

A CPI of exactly 1.0 is on budget. Values between 0.9 and 1.1 are generally considered acceptable. Below 0.8 signals a serious cost overrun requiring corrective action. Above 1.2 may indicate under-reporting of actual costs.

Can I use this calculator without knowing BAC?

Yes. BAC (Budget at Completion) is optional — it enables the Estimate at Completion (EAC) projection. CV and CPI are computed from EV and AC alone.

Cost Variance Calculator (EVM)

Name: Cost Variance Calculator (EVM)
Availability: InStock
Author: Nham Vu

Enter Earned Value (EV) and Actual Cost (AC) to calculate Cost Variance (CV) and Cost Performance Index (CPI) for your project.

Project Cost Inputs

Enter values in your project's currency.

Budget at Completion (BAC) — optional

Total approved budget. Used for EAC projection.

Earned Value (EV) *

Budgeted value of work completed to date.

Actual Cost (AC) *

Real money spent on the project to date.

Enter EV and AC, then click Calculate.

EVM Formulas

CV= EV − AC

CPI= EV ÷ AC

EAC= BAC ÷ CPI

VAC= BAC − EAC

Summary

Enter Earned Value (EV) and Actual Cost (AC) to calculate Cost Variance (CV) and Cost Performance Index (CPI) for your project.

How it works

Enter the Budget at Completion (BAC) — the total approved project budget.
Enter the Earned Value (EV) — the budgeted cost of work actually performed so far.
Enter the Actual Cost (AC) — the real money spent on the project to date.
The calculator computes CV (EV − AC) and CPI (EV ÷ AC) instantly.
Read the color-coded status to see if you are over budget, on budget, or under budget.

Use cases

Track whether a software development project is overspending mid-sprint.
Report EVM metrics to stakeholders in weekly project status meetings.
Compare CPI across multiple project phases to spot cost trends early.
Determine if current spending rate will exhaust the budget before delivery.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu