The EAC Calculator figures out the Estimated at Completion (EAC), which is the total cost you expect for a project by the time it’s done. It looks at what you’ve spent so far and how well the project is going to give you a final number. This tool falls under the category of project management calculators, making it perfect for managers, business owners, or anyone keeping a project on budget.
Why is this helpful? Projects don’t always stick to the original plan—costs can go up or work can slow down. The EAC Calculator helps you see the real cost ahead, so you can adjust plans or avoid surprises. It’s great for real-life decisions, like managing money, finishing on time, or keeping clients happy. Plus, it’s reliable for important financial choices—like staying profitable or fixing budget problems. Want to know how it works? Let’s check out the formulas next.
Formula for EAC Calculator
The EAC Calculator has a few ways to predict costs, depending on your project:
1. Future Matches Planned Performance
EAC = BAC / CPI
Where:
- BAC = Budget at Completion (total planned budget)
- CPI = Cost Performance Index = EV / AC
- EV = Earned Value = (percent complete × BAC)
- AC = Actual Cost (money spent so far)
2. No Recovery from Current Issues
EAC = AC + (BAC – EV)
Where:
- AC = Actual Cost
- BAC = Budget at Completion
- EV = Earned Value
3. Using Cost and Schedule Performance
EAC = AC + [(BAC – EV) / (CPI × SPI)]
Where:
- AC = Actual Cost
- BAC = Budget at Completion
- EV = Earned Value
- CPI = Cost Performance Index = EV / AC
- SPI = Schedule Performance Index = EV / PV
- PV = Planned Value (budgeted cost of work planned so far)
4. Custom Efficiency for Future Work
EAC = AC + [(BAC – EV) / custom CPI]
Where:
- AC = Actual Cost
- BAC = Budget at Completion
- EV = Earned Value
- custom CPI = your chosen efficiency rate
These formulas come from project management standards, like the PMBOK guide. Each one fits a different situation—use the first if things will get better, the second if they won’t, the third for both cost and time, or the fourth for your own guess. Now, let’s simplify it with a table.
Quick Reference Table for EAC
Why calculate every time? This table shows EAC for common project numbers, assuming BAC = $10,000.
| AC ($) | EV ($) | CPI | SPI | EAC ($) (Formula 1) | EAC ($) (Formula 2) |
|---|---|---|---|---|---|
| 4,000 | 5,000 | 1.25 | 1.0 | 8,000 | 9,000 |
| 6,000 | 4,000 | 0.67 | 0.8 | 14,925 | 12,000 |
| 3,000 | 3,000 | 1.0 | 1.0 | 10,000 | 10,000 |
How to Use the Table
- Find your AC and EV.
- Check CPI and SPI (if needed).
- Pick the EAC from Formula 1 or 2.
This table helps with searches like “EAC for $6,000 spent.” For exact numbers, use the formulas. Next, let’s try an example.
Example of EAC Calculator
Suppose your project has a BAC of $20,000. You’ve spent $8,000 (AC), and the earned value (EV) is $10,000. The CPI is 1.25. You want the EAC assuming future performance matches the plan. Here’s how:
- Plug into Formula 1:
EAC = BAC / CPI
EAC = 20,000 / 1.25 - Calculate:
20,000 / 1.25 = 16,000
So, the EAC is $16,000. This means you’ll finish under budget if things keep going well. It matches project math and helps you plan.
Most Common FAQs
Calculating EAC shows you the total cost you’ll end up with, based on how the project’s going. It’s key for knowing if you’ll stay on budget, so you can fix problems or tell clients what to expect.
You get AC from your spending records, EV from how much work is done times the BAC, and BAC from your original plan. CPI and SPI come from dividing EV by AC or PV—track these as you go.
Use Formula 1 if you think things will improve, Formula 2 if they won’t, Formula 3 if time matters too, or Formula 4 if you have a specific guess for future work. Pick based on your project’s trends.