Repair vs Replace Calculator

The calculator requires the repair cost to be less than 50% of the full replacement cost AND more than 25% of the item's expected total lifespan to remain after repair. Both thresholds must pass — a cheap repair on an item that's nearly at the end of its expected life still gets flagged against repairing, and a repair on a nearly-new item that costs more than half of replacement also fails the test.

It adds the ongoing annual maintenance cost for the current item, multiplied by however many years of remaining life you have, to the one-time repair cost, then divides that combined total by remaining life. So it's an all-in annualized cost of keeping the repaired item running, not just the repair bill spread out.

It divides the repair cost by the annual cost difference between the new-item path and the repair path (cost per year new minus cost per year repaired). If replacing costs more per year than repairing, this tells you roughly how many years it takes for that per-year savings to offset what you spent on the repair; if repairing isn't actually cheaper per year, break-even is reported as zero.

The cost-per-year figures are a pure economic comparison, while Repair Recommended additionally enforces the 50%-of-replacement-cost and 25%-remaining-life rules of thumb regardless of what the annualized costs say. It's possible for repairing to show a lower cost per year while still failing the "worthwhile" test if the item is nearly at the end of its expected lifespan.