What is ROI (return on investment)?
Return on investment (ROI) is a simple performance measure: how much you gained or lost relative to what you put in. A positive ROI means the outcome was worth more than the cost; a negative ROI means you lost money relative to the starting amount. People search for an ROI calculator when they want that percentage quickly — for investments, courses, campaigns, or any cash outlay with a measurable result.
How it works
Enter the money you spent (initial investment) and either the final value of what you have now or the gain/loss amount. The calculator computes simple ROI as a percentage. If you also enter a holding period in years, it annualizes the return so a 35% gain over 18 months is not treated the same as 35% over three years.
Formula
How to use ROI Calculator
- Enter the initial investment (what you spent).
- Choose final value or gain/loss, then enter that amount.
- Optionally add the holding period in years for annualized ROI.
- Read the ROI percentage, dollar gain or loss, and annualized figure if provided.
Worked examples
Concrete numbers and cases you can check against the tool above.
Spend $2,000, later worth $2,700 after 18 months
Simple ROI = (2700 − 2000) / 2000 = 35%. Annualized ROI is (1.35)^(1/1.5) − 1 ≈ 22% per year. A 35% gain in three months is a very different annualized result than 35% in three years — always look at both.
Negative ROI on a $1,000 outlay worth $800
ROI = (800 − 1000) / 1000 = −20%. Profit in dollars is −$200; ROI states that loss as a percent of capital. If the holding period was 2 years, annualized ROI is even lower than −20% simple — the calculator shows both when you enter years.
Marketing spend vs revenue (ROI, not ROAS)
You spend $5,000 on a campaign and attribute $8,000 revenue. Simple ROI = (8000 − 5000) / 5000 = 60% if you treat revenue as final value. ROAS would be 8000/5000 = 1.6× and does not subtract cost the same way. Include product cost in the “final” or “gain” inputs if you want a truer ROI.
ROI vs profit
Profit is usually a dollar amount (revenue minus costs, or final value minus cost). ROI expresses that same idea as a percentage of the original investment. A $500 profit on a $1,000 outlay is 50% ROI; a $500 profit on a $10,000 outlay is only 5% ROI. Both made $500, but the efficiency of the capital was very different.
ROI vs ROAS
ROAS (return on ad spend) is common in advertising: revenue attributed to ads divided by ad spend. ROI typically subtracts cost from the result first, so it reflects net return relative to investment. A campaign can show strong ROAS and still weak ROI once product cost, fees, or fulfillment are included. This calculator is for classic ROI, not a full ROAS attribution model.
Interpreting positive and negative ROI
Positive ROI means the final value exceeded the cost. Negative ROI means you ended below the initial outlay — for example, buying something for $1,000 that later is worth $800 is −20% ROI. Zero ROI means you broke even on value. Annualized ROI helps compare results across different time spans; it is not a guarantee of future returns.
When to use ROI Calculator
A spreadsheet works, but a dedicated return on investment calculator keeps the formula consistent and makes annualized comparisons obvious. That matters when one option ran for six months and another for two years — simple ROI alone can mislead.
Common use cases
- Compare two project outcomes on an annualized basis.
- Check marketing spend against attributed revenue (simple ROI, not ROAS).
- Evaluate a course or certification against an income change.
- Summarize a personal investment’s simple return before diving into IRR or CAGR models.
Inputs and outputs
- Currency amounts for cost, final value, or gain
- Optional holding period in years (supports fractions such as 1.5)
Privacy
This tool runs entirely in your browser. Amounts you enter never leave your device — nothing is uploaded to our servers.
Frequently asked questions
- What is the ROI formula?
- Simple ROI is ((final value − initial cost) ÷ initial cost) × 100. If you only know the gain, final value is initial cost plus gain.
- What is annualized ROI?
- It restates the total return on a per-year basis so investments held for different lengths are easier to compare. It assumes a steady compounding path for the math — real markets vary.
- Does ROI include ongoing costs?
- Only if you fold them into the amounts you enter. The formula uses the inputs you provide; it does not invent fees or taxes.
- Is this investment advice?
- No. It is a simple math tool for return on investment calculations. It does not account for risk, taxes, or liquidity.