Goal Seek vs Solver in Excel: Which One Do You Need?

Goal Seek vs Solver comes down to how many inputs can change and whether there are limits. Goal Seek changes one input cell until one formula reaches an exact target. Solver changes several input cells at once, keeps to the limits you set, and can find the highest or lowest possible result. This guide is for analysts, students and job seekers who need to pick the right what-if tool, and it solves the same small model with both.

Goal Seek vs Solver at a glance#

Both tools work backwards from a result you want to the inputs that produce it. The table shows where they differ.

Goal Seek is built into desktop Excel for Windows and Mac. Solver ships with desktop Excel too, but it's switched off until you turn it on once under File > Options > Add-ins (Windows) or Tools > Excel Add-ins (Mac).

The model both tools will use#

A small workshop makes mugs and bottles. Both products use machine time, and the machine is available for 400 hours a month:

Profit in B7 is (15 − 6) × 300 + (25 − 13) × 200 − 3,000 = 2,700 + 2,400 − 3,000 = 2,100. Hours used in B8 are 150 + 200 = 350. SUMPRODUCT multiplies matching cells and adds the results; the SUMPRODUCT guide explains how it handles the price-minus-cost step.

Both tools need this kind of model: inputs in their own cells and formulas that depend on them. Neither works on typed numbers.

The same model solved both ways#

Goal Seek: what mug price gives a profit of 3,000?#

This question has one input (the mug price) and one exact target, so Goal Seek fits:

1. Go to Data > What-If Analysis > Goal Seek.
2. Set cell: B7. To value: 3000. By changing cell: B2.
3. Click OK, then OK again to keep the result.

Goal Seek sets the mug price to 18. The mugs now earn 12 each, so 12 × 300 + 2,400 − 3,000 = 3,000. That's a price rise of (18 − 15) ÷ 15 = 20%. The full walkthrough is in the Goal Seek guide.

Solver: which mix of units earns the most?#

Now ask a different question: how many mugs and bottles should the workshop make to earn the most profit? Mug demand is at most 500 a month, bottle demand at most 300, and machine hours are capped at 400. Two inputs, three limits and no fixed target: that's Solver's job.

1. Open Data > Solver.
2. Set Objective: $B$7. To: Max.
3. By Changing Variable Cells: $B$4:$C$4.
4. Add these constraints: $B$8 <= 400, $B$4 <= 500, $C$4 <= 300, and $B$4:$C$4 int for whole units.
5. Tick Make Unconstrained Variables Non-Negative and choose Simplex LP, because every formula is a simple multiplication.
6. Click Solve, then Keep Solver Solution.

Solver returns 500 mugs and 150 bottles, using exactly 400 hours, for a profit of 4,500 + 1,800 − 3,000 = 3,300. Each mug earns 9 for half an hour of machine time (18 an hour), while each bottle earns 12 for a full hour. So Solver fills mug demand first and gives the remaining 150 hours to bottles. Goal Seek can't answer this question at all: it can't change two cells, and it can't respect the 400-hour limit.

The Solver guide covers the dialog box and the three solving methods in more depth.

When to use Goal Seek#

Use Goal Seek when the question has the shape "what input gives exactly this result?":

• One input, one target. The price for a profit goal, the growth rate for a sales target, the interest rate for a payment.
• Hard-to-rearrange formulas. A loan payment built with PMT is awkward to solve by hand. Goal Seek just tries values until it lands. See how the PMT function works.
• Quick checks in a meeting or a test. It takes seconds and needs no add-in.

A common example is the break-even point: set profit to 0 by changing price or units. The break-even analysis guide shows both the Goal Seek and the formula version.

When to use Solver#

Use Solver when the question has more than one moving part:

• Several inputs change together. Product mix, staff hours across days, a budget split across channels.
• There are limits. Machine hours, a maximum budget, minimum stock, whole numbers only, or yes/no choices (binary).
• You want the best result, not a set number. Highest profit, lowest cost, shortest time.

Solver can also hit an exact value with its Value Of option, so it can do any Goal Seek task. It's just slower to set up for simple ones.

Common mistakes with Goal Seek and Solver#

Most problems with both tools come from how the sheet is built, not the tools themselves:

1. Pointing at a typed number. The Set cell or objective must contain a formula. The changing cells must contain values, not formulas.
2. Inputs that don't feed the result. If B2 isn't used anywhere in B7's formula, nothing either tool tries can change the result.
3. Forgetting non-negative units. Without that box ticked, Solver may suggest making −50 bottles.
4. Using Simplex LP on non-linear models. If a formula multiplies two changing cells, such as price × units when both change, choose GRG Nonlinear instead.
5. Expecting the answer to update. Both tools type fixed values. Change the costs tomorrow and you must run them again.
6. Ignoring tiny rounding. Goal Seek stops when it's very close, so 17.99999 can appear instead of 18. Round it or retype it.

A third option: a reverse formula#

When the maths is simple, a formula beats both tools because it updates by itself. The Goal Seek question above can be rearranged:

=B3+(B7+B6-(C2-C3)*C4)/B4

Read it as: the mugs must earn the target (3,000) plus fixed costs (3,000), minus what the bottles already earn (2,400). That's 3,600 across 300 mugs, or 12 profit per mug. Add the unit cost of 6 and the price is 18, the same as Goal Seek. Change any cost and the price updates at once. The savings goal calculator uses the same idea with financial functions.

Our recommendation#

Reach for Goal Seek first when one input must hit one exact number. It's fast, built in and easy to explain. Switch to Solver as soon as two or more inputs change, you have limits, or the goal is "as high as possible" or "as low as possible". And if you can rearrange the formula yourself, write it: a live formula never goes stale.

In short: Goal Seek for one input and one target, Solver for many inputs and limits, a formula when the maths allows.

Practise it#

Both tools only work on a well-built model, so practise building one. Practise a department budget in a live spreadsheet to set up inputs and totals that formulas can depend on, then practise percentages and percent change to describe results like "a 20% price rise". Each lesson checks your formula as you type. Then try the exercise on this page to work out the target price with a reverse formula.