Justifying a software purchase usually comes down to one question: does the time it saves outweigh what it costs? This calculator turns "it saves everyone a few hours a week" into an actual dollar figure, so that comparison is explicit rather than a gut feeling.
How it works
Time saved is converted to a dollar value by multiplying hours saved per week by an hourly value of that time, ideally a loaded rate (salary plus benefits and overhead), not just a base wage, since that's closer to what an hour of someone's time actually costs the business.
That weekly value is multiplied by 52 weeks and by the number of people using the tool, to get a total annual value of time saved across the team.
Subtracting the tool's annual cost from that value gives the net annual value: positive means the tool is paying for itself and then some. Dividing cost by the monthly value saved gives the payback period: how long until the tool has paid for itself.
A worked example
A tool costing $2,400/year that saves one person 5 hours a week, valued at $50/hour, returns about $13,000/year in time value, a net annual value of roughly $10,600, an ROI of about 442%, and a payback period of about 2.2 months.
Questions people ask
How do I pick an hourly value for someone's time?
A reasonable estimate is annual salary divided by roughly 2,000 working hours, then adjusted upward by 20-30% to account for benefits and overhead. This "loaded" rate reflects what an hour actually costs the business, not just take-home pay.
What if the tool doesn't save time but improves quality or reduces errors?
This calculator is built around time savings specifically. For quality or error-reduction benefits, you'd need to estimate their dollar impact separately (e.g. cost of a typical error avoided × number of errors prevented) and add that to the value saved manually.
Is a payback period of a few months good?
Under 12 months is generally considered a strong case for approving a purchase; under 3 months is an easy yes for most budget holders. Longer payback periods aren't necessarily bad, but they warrant more scrutiny of the time-savings assumption.
Should I trust an ROI over 400%?
Treat a very high ROI as a signal to double-check your hours-saved estimate rather than as a guaranteed result. It's a common failure mode to overestimate how much time a tool actually saves in practice versus how much it saves in theory. Conservative estimates make for a more defensible business case.