Free ROI Calculator — Return on Investment
Enter what you put in and what you got back — from an ad campaign, a piece of equipment, anything — to see your return as a clean percentage.
Example result
- You enter
- Amount invested
- $1,500
- Amount returned
- $1,950
- You get
- Net gain
- $450
- ROI
- 30%
Fictional numbers, to show how the result is laid out.
How it works
ROI is the simplest way to compare two very different kinds of spending on equal footing: (Amount Returned − Amount Invested) ÷ Amount Invested × 100. A $500 ad spend that drove $2,000 in revenue and a $50,000 piece of equipment that saved $60,000 in labor over its life both reduce to the same kind of percentage, which is what makes ROI useful for deciding where the next dollar should go.
The calculation itself doesn't know anything about time, which is the detail that trips people up when comparing options. A 20% ROI realized in one month is a completely different opportunity than a 20% ROI that took three years to materialize — always note the time period alongside the percentage, especially when putting two ROI figures side by side.
A worked example: spending $1,500 and getting $1,950 back is a net gain of $450, so ROI is $450 / $1,500 = 30%. The gain should be profit, not revenue, and the cost should include everything the investment took, such as tools and your own time.
State the time period beside the percentage. A 30% return over three months is very different from 30% over three years. If you want to know how long it takes to earn the money back, divide the investment by the profit it produces each month.
Who uses this
| Business type | How it's used |
|---|---|
| Marketing agencies & freelancers | Check the return on an ad campaign or client project against what it cost to run. |
| Restaurants & cafes | Check whether a new espresso machine, renovation, or delivery partnership paid for itself in added revenue. |
| Retail stores | Evaluate whether new fixtures, signage, or a POS system upgrade returned more than it cost. |
| E-commerce sellers | Check the return on ad spend for a campaign against the revenue it generated. |
| Salons & spas | Check whether new equipment (chairs, treatment beds) or a rebrand paid for itself in added bookings. |
| Gyms & fitness studios | Check whether new equipment or a marketing push paid for itself in added memberships. |
| Contractors & tradespeople | Check whether a new tool, truck, or certification paid for itself in added or faster-completed jobs. |
Frequently asked questions
Q.Does ROI account for how long the investment took?
No — this is a simple ROI calculation, not annualized. A 20% ROI over one month is very different from 20% over three years, so factor in the time period separately when comparing options.
Q.What counts as 'amount returned'?
The total value you got back, including the original investment. If you spent $5,000 on ads and it drove $6,500 in revenue, $6,500 is your return — the calculator subtracts the investment to find your net gain.
Q.Is this the same as a return on investment estimator?
Yes — ROI calculator, return on investment calculator, and ROI estimator all describe the same calculation: net gain divided by cost, expressed as a percentage.