How to Use Goal Seek in Excel Formula

Goal Seek in Excel lets you find the exact input needed to produce a desired result from a formula. Instead of guessing values, Excel adjusts one variable automatically until the formula reaches your target.

It is commonly used to solve equations, calculate percentages, and test financial scenarios such as savings, repayments, or interest rates.

Use Goal Seek quickly

Goal Seek sets a formula to a target value by changing one input cell.

1. Select the formula cell.
2. Open Goal Seek from Data → What-If Analysis, or type “Goal” in the Tell Me box.
3. Enter the target value.
4. Select the input cell to change.
5. Click OK.

Excel calculates the required input and updates the worksheet with the result.

Goal Seek example in Excel

Here is a quick video to show you exactly how to use Goal Seek to solve an equation iteratively.

In this example, you use a budget spreadsheet to work out how much to save each month. You set the cash amount left over as the target and enter zero as the goal.

You open Goal Seek by typing “Goal” in the Tell Me box, then choose long-term savings as the input to change. Excel adjusts the savings amount until the cash balance reaches zero.

What Goal Seek does in Excel

Goal Seek is a built-in Excel tool that works backwards from a result. Instead of changing inputs manually, you tell Excel the result you want, and it calculates the input needed to reach it.

It works by adjusting one value that feeds into a formula. Excel keeps recalculating until the formula returns the target result. This removes the need for trial and error when working with linked calculations.

Goal Seek is commonly used in budgeting, loan calculations, and percentage-based models. It is especially useful when you know the outcome you want but do not know the number required to get there.

Using Goal Seek with formulas

Goal Seek works with a formula that already returns a result. Excel then works backwards to find the input needed to produce your chosen value.

It relies on three parts:

• Formula cell — the result you want to control
• Target value — the result you want Excel to reach
• Input cell — the value Excel is allowed to change

The input cell must be part of the formula. Goal Seek then recalculates until the result matches the target as closely as possible.

This is useful for interest rates, savings targets, repayment amounts, and percentage-based formulas.

How it solves equations

Goal Seek effectively solves equations inside Excel without requiring algebra. Instead of rearranging a formula, you define the result you want and let Excel determine the input that satisfies it.

For example, if a formula calculates profit based on units sold, you can set profit to zero and let Excel calculate how many units are needed to break even. This works even when the formula is complex.

This makes Goal Seek useful for percentage targets, interest rate calculations, and other scenarios where you need to reach a specific result but do not know the required input.

Using Goal Seek with multiple cells or automation

Goal Seek works with one changing cell at a time. It cannot directly adjust multiple inputs in a single run.

For larger models, the usual options are:

• run Goal Seek manually for each row or case
• structure the worksheet so one input drives the result
• use a VBA macro to loop through rows automatically
• use Solver when multiple changing cells or constraints are involved

A VBA loop can run Goal Seek repeatedly across a range, which is much faster than doing each case by hand.

Always check the result, because Goal Seek uses an iterative method and may return an approximate answer.

Related: Top 5 Uses of Microsoft Excel in the Office