Goal Seek in Excel: Step-by-Step Guide with Examples

Goal Seek finds the input value needed to achieve a specific result. Instead of asking "What will happen?", it answers "What do I need to make this happen?"

What is goal seeking analysis?

Goal seeking analysis reverses a normal calculation: instead of computing an output from known inputs, you fix the output and solve for the input. Excel's Goal Seek does this numerically — it tries values in the changing cell, checks the formula result, and homes in on the target through iteration, usually in under a second.

Normal calculation:  inputs → formula → result
Goal seeking:        desired result → formula → required input

Example question:
"What price do I need to charge to reach $100,000 profit?"

How do I use Goal Seek step by step?

Build a formula that depends on the input you want to solve for, then open Goal Seek from the Data tab and fill in the three boxes. The "Set cell" must contain a formula, and the "By changing cell" must contain a plain number that the formula depends on — directly or through other formulas.

1. Create a formula whose result depends on one input cell
2. Data tab → What-If Analysis → Goal Seek
3. Set cell: the cell containing the formula
4. To value: the result you want (a typed number, not a reference)
5. By changing cell: the single input Excel may adjust
6. Click OK — review the result, then OK to keep it or Cancel to revert

Worked example: maximum loan for a $2,000 payment

The classic Goal Seek use case: you know the monthly payment you can afford and want the loan amount that produces it. Build the payment with PMT, then let Goal Seek solve for the principal.

Scenario: Maximum monthly payment is $2,000
Question: What's the maximum loan amount?

Setup:
Cell B1: Loan Amount (to be calculated)
Cell B2: Interest Rate = 5%
Cell B3: Years = 30
Cell B4: =PMT(B2/12, B3*12, -B1)   // monthly payment

Goal Seek:
1. Data → What-If Analysis → Goal Seek
2. Set cell: B4 (monthly payment)
3. To value: 2000
4. By changing cell: B1 (loan amount)
5. Click OK

Result: B1 shows maximum loan amount (~$372,563)

Tip: the -B1 in PMT keeps the payment positive so you
can type a positive target value.

How do I find a break-even price with Goal Seek?

Build a profit formula from units, price, variable cost, and fixed costs, then use Goal Seek to set that profit cell to zero by changing the price cell.

Setup:
Cell B1: Units Sold = 1000
Cell B2: Price per Unit = 50 (to find)
Cell B3: Variable Cost = 30
Cell B4: Fixed Costs = 15000
Cell B5: =B1*(B2-B3)-B4  // Profit formula

Goal Seek to Break Even:
Set cell: B5 (profit)
To value: 0 (break even)
By changing: B2 (price)

Result: Price needed to break even = $45

How do I find the score needed on a final exam with Goal Seek?

Set the average formula as the Set cell, type your target average as the To value, and let Goal Seek solve for the unknown exam score in the By changing cell.

Scenario: Need 90% average, what do you need on final exam?

Setup:
Cell B1: Test 1 = 85
Cell B2: Test 2 = 88
Cell B3: Final Exam = 0 (to calculate)
Cell B4: =AVERAGE(B1:B3)

Goal Seek:
Set cell: B4 (average)
To value: 90
By changing: B3 (final exam score)

Result: Need 97 on final exam

How do I find the units needed to hit a profit target?

Set your profit formula as the Set cell, type the target profit as the To value, and let Goal Seek solve for the unknown unit count in the By changing cell.

Question: How many units to sell for $50,000 profit?

Setup:
Cell B1: Units (to find)
Cell B2: Price = 100
Cell B3: Cost = 60
Cell B4: Fixed Costs = 10000
Cell B5: =B1*(B2-B3)-B4  // Profit

Goal Seek:
Set cell: B5
To value: 50000
By changing: B1

Result: Need to sell 1,500 units

What are Goal Seek's limitations?

Goal Seek changes exactly one input to hit exactly one target — no more. It can't apply constraints (like "units must be whole numbers"), it stops at the first solution it finds even when several exist, and it may fail entirely if no input value can reach the target or the formula isn't smooth.

• Single variable: only ONE "By changing cell" — you can't adjust price and volume together
• Single target: one Set cell, one To value — no optimizing "as large as possible"
• No constraints: results can be negative, fractional, or unrealistic
• First solution wins: if multiple inputs satisfy the target, you get whichever the iteration reaches first
• May not converge: "may not have found a solution" usually means the target is mathematically unreachable — check the formula logic

Goal Seek vs Solver: which should I use?

Use Goal Seek for quick one-input, one-target questions — it needs no setup or add-in. Use Solver when you have multiple changing cells, constraints, or want to maximize/minimize rather than hit an exact value. Solver is a free add-in (File → Options → Add-ins) and supersedes everything Goal Seek does.

See the full comparison in Goal Seek vs Solver, or jump straight to the Excel Solver guide for optimization with constraints. Goal Seek's siblings — Scenario Manager and Data Tables — are covered in What-If Analysis in Excel.

When should I use Goal Seek?

Reach for Goal Seek whenever you have a single formula and want to solve backward for the one input that produces a specific target: break-even points, required pricing, needed sales volume, or loan and investment sizing.

• Finding break-even points
• Determining required pricing
• Calculating needed sales volume
• Budget planning and forecasting
• Loan and investment calculations