What is factory downtime costing you?

The cost of downtime is what one hour of an unplanned stop takes out of your business: the margin on the parts you did not make, plus the wages and overhead you paid anyway. For a mid-size Indian line it usually runs into thousands of rupees per hour, and because nobody writes it down as one line item, owners tend to underestimate it badly.

How the calculator works

The calculator adds three costs that all run while the line is stopped, then scales the result to a month and a year:

Cost per downtime hour = (parts per hour × gross margin per part) + labour cost per hour + overhead per hour

Then:

• Per month = cost per downtime hour × unplanned downtime hours per month
• Per year = per month × 12
• Recoverable with monitoring = per year × the share of downtime you think you could recover (slider, 0–50%)

What each input means:

• Parts produced per hour. The good output the line makes when it runs. Use the real running rate, not nameplate speed.
• Gross margin per part (₹). Sale price minus the variable cost of the part (material, consumables, per-piece power). Full sale price overstates the loss, because you never bought material for parts you never made.
• Loaded labour cost per hour (₹). What the whole crew on the stopped line costs per hour, including PF, ESI and bonus, not one person's basic wage.
• Overhead per hour (₹). Rent, depreciation, supervision, base power load and interest that keep running while nothing ships.
• Unplanned downtime (hours per month). Breakdowns, waiting for material, changeovers that ran long. Leave out planned stops such as scheduled maintenance and holidays.
• Downtime you could recover with monitoring (%). Your own estimate of how much of that downtime you could win back if you saw stops as they happen. The default is 20%, which is an assumption, not a measured figure.

Nothing else is added: no repair bill, scrap or late-delivery penalty, so if those apply, your real number is higher.

Worked example (India)

A 9-person press and moulding cell in Haryana that sells everything it makes. Wages are the Haryana minimum wages from gazette notification No. 2/25/26-2 Lab (9 April 2026). All other figures are assumptions for illustration.

Look at how the ₹6,518 splits up. Lost margin is ₹3,600 (55%), overhead is ₹2,000 (31%) and labour is only ₹918 (14%). Wages are low in Indian plants, so owners who think of downtime as "people standing around" miss most of the cost. The expensive part is the output that never got made.

What typical numbers look like

• Hours lost. Siemens' True Cost of Downtime 2024 found that the average large plant loses 27 hours a month to unplanned downtime, down from 39 in 2019, across about 25 incidents a month (AEMT summary of the Siemens report). The survey covers large plants of the world's biggest manufacturers, not Indian MSMEs.
• Scale at the top end. The same report puts an idle line at a major automotive plant at up to $2.3 million per hour and estimates that unplanned downtime costs the 500 biggest companies about 11% of revenue (AEMT/Siemens). These are multinational figures, not Indian mid-size ones.
• How much running time is lost. For discrete manufacturers, 60% OEE is fairly typical and 85% is world class (Lean Production). Data from 3,500+ machines in 50+ countries shows most plants sit at 55–60% OEE (Evocon). Part of that gap is downtime and part is slow running.
• India by sector. A 2026 benchmark from a monitoring vendor gives typical OEE of 40–58% for Tier 2–3 auto suppliers, 40–55% for textiles and garments and 45–60% for food processing (TeepTrak). The source sells monitoring, so read these as indicative.
• Indian MSME downtime hours. We found no credible public source for typical unplanned-downtime hours per month in Indian MSMEs. Measure your own rather than borrow a figure.

What this number does not tell you

• Whether you can catch up. The formula assumes every lost part is lost for good, which is true only if you are sold out or the stopped machine is your bottleneck. If you can make the parts up on overtime next week, the real cost is closer to the overtime premium plus overhead. If a non-bottleneck machine stops and the constraint keeps running, the cost can be close to zero.
• How much of the overhead is real cash. Rent and depreciation are paid whether the line runs or not. They become a real loss only when the stop cuts what you can sell.
• Costs it leaves out. Repair parts, scrap made during restart, rushed freight and customer penalties are not in the formula.
• Whether your downtime figure is honest. Logbooks round off short stops. The same vendor benchmark reports that recorded downtime typically rises 30–50% when plants move from manual to automated tracking (TeepTrak), so a hand-logged figure is probably low.
• The recovery percentage is a guess. The slider is your own assumption. Nothing in the calculator measures it.

Related guides

• What One Hour of Downtime Actually Costs an Indian Factory (₹)
• The Real Cost of Factory Downtime (and How to Measure It)
• OEE Explained for Indian Factories (with a Rupee Example)
• Factory Downtime, Theft & Accident Statistics in India (2026)
• Production Disruptions: Know in Minutes, Not at Shift-End

FAQ

How do you calculate the cost of downtime per hour? Multiply the parts you would have made in an hour by the gross margin per part, then add the hourly cost of the idle crew and the hourly overhead. For example, 300 parts × ₹12 + ₹918 labour + ₹2,000 overhead = ₹6,518 per hour.

What is the cost of downtime per hour in India? There is no single national figure. It depends on your output rate and margin. With Indian wage levels, a mid-size line typically comes out in the thousands to low tens of thousands of rupees per hour, and most of that is lost margin rather than wages.

Should I use sale price or margin in a downtime cost calculation? Use margin: sale price minus the variable cost of the part. You never bought the material for parts you did not make, so the full sale price overstates the loss.

How many hours of unplanned downtime is normal? Siemens reports 27 hours a month for the average large plant worldwide. No credible public figure exists for Indian MSMEs, and hand-kept logs usually undercount short stops, so measure your own floor.

Is planned maintenance counted as downtime in this calculator? No. Enter only unplanned stops: breakdowns, waiting for material and overrunning changeovers.

Want this measured on your own floor instead of estimated? Leave an email or phone in the form below.