When the ROI Calculator seems to misbehave, the cause is usually one of two things: something stopped the tool from running, or it ran but the result is not usable. This guide starts with the fastest checks, then walks through the common problems and exact fixes.
Quick Checks First
- Refresh the page - a stalled session is the most common cause of nothing happening.
- Confirm the input is not empty and actually contains what you meant to submit.
- Try the smallest possible input; if that works, the issue is size, not the tool.
- Turn off browser extensions that block scripts, then reload and test again.
- Update or switch browsers if the problem repeats across sessions.
Common Problems and How to Fix Them
The percentage looks too high.
Check that you used net gain rather than gross gain - subtract the cost before dividing.
My two projects are not comparable.
ROI ignores time, so normalise both results to the same period before ranking them.
It shows a negative number.
That is a loss - the same formula reports negative returns honestly.
Costs after the launch are missing.
Add follow-up spending to the cost side so the percentage reflects the whole outlay.
I want to use it for a multi-year project.
Yes, but note the horizon - a 30% return over one year and over five years mean different things.
I expected investment advice from this tool.
No - it measures what already happened rather than predicting future performance.
When It Works but the Output Is Poor
If the tool runs fine but the result misses, the problem is almost always the brief, not the software:
- Forgetting to subtract the cost first
- Comparing returns over different periods
- Ignoring costs after the purchase
- Reading ROI as a future guarantee
How to Stop It Happening Next Time
- Keep a saved prompt template for every task you repeat.
- Change one setting per generation so causes stay obvious.
- Run a two-minute sanity test with known input after any update.
- Note every failure and its fix; a short troubleshooting log pays for itself.
Still Stuck?
Reproduce the problem with the smallest possible input and note the exact steps that triggered it. A one-line description of what you did, what you expected and what happened is enough to get a precise answer from support or a colleague.
Frequently Asked Questions
What is the ROI formula?
ROI equals (gain minus cost) divided by cost, multiplied by 100 to give a percentage.
Can ROI be negative?
Yes - when the gain falls below the cost the result is negative, showing a loss.
Does ROI account for time?
No - compare returns over equal periods, or note the timeframe next to the figure.
Is my data stored?
No - calculations run in your browser with nothing saved.
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