Cost of Downtime Calculator

Put numbers on an outage. This adds up the revenue you lose, the staff time you waste and the cost of putting things right, then shows it as a total and per minute of downtime.

An example is filled in. Change every field to match your business.

Your inputs

Revenue

Currency

The currency to show results in.

Yearly revenue affected by the outage $

Revenue from the part of the business the outage takes down. If only your online store is affected, use its yearly revenue, not the whole company's.

Operating hours per week

Use 168 for an always-on service. Use your real opening hours for a business that only earns at certain times.

Share of revenue actually lost %

How much of the missed revenue is gone for good. Lower this if customers usually come back and buy later, or buy through another channel.

The outage

Downtime length

How long the outage lasted, in the unit you pick next.

Unit

The unit for the downtime length above.

Staff impact

People who cannot work during the outage

Staff whose job depends on the system being up.

Average staff cost per hour $

Fully-loaded hourly cost per person: wage plus employer taxes and overheads. A rough guide is yearly salary ÷ 1,500.

How much of their work is blocked %

100% if they cannot do anything useful. Lower it if they can switch to other tasks.

Recovery

One-off recovery costs $

Extra spending caused by this outage: overtime, emergency vendor support, SLA credits you owe customers, replacement hardware.

What it costs

Total cost of this outage —

Lost revenue + lost productivity + recovery costs.

Lost revenue —

Revenue per hour × hours of downtime × the share you do not recover.

Lost productivity —

Blocked staff × their hourly cost × hours of downtime × the share of work blocked.

Recovery costs —

The one-off figure you entered, carried straight through.

Cost per hour of downtime —

Total cost ÷ hours of downtime. Useful for judging how much faster recovery is worth.

Cost per minute —

The same, per minute.

Yearly cost if this happened monthly —

This outage's cost × 12 — a sense of the yearly stakes if it is a recurring problem.

This is a floor. It leaves out reputational damage and customers who leave for good, which are real but hard to estimate reliably.

What goes into the cost of an outage

Lost revenue. Sales or billing you miss while the service is down, minus anything you recover later or through other channels.
Lost productivity. The wage cost of everyone who is paid but cannot do their job until the system is back.
Recovery costs. Overtime, emergency support contracts, SLA credits owed to your own customers, hardware you have to replace.
Reputation and churn. Real, but not reliably measurable — kept out of the total here. Add your own estimate for a serious incident.

How the numbers are worked out

Revenue per hour = yearly affected revenue ÷ (operating hours per week × 52). Lost revenue = revenue per hour × hours of downtime × share actually lost. Lost productivity = blocked people × hourly cost × hours of downtime × share of work blocked. Total is the sum of those plus recovery costs, and cost per hour and per minute divide the total by the outage length.

Using the per-minute figure

Once downtime has a price per minute, reliability spending stops being a guess. If an outage costs $400 a minute and a change to your deploy process would cut a typical recovery from 45 minutes to 20, that change is worth about $10,000 every time it is used. The same logic applies to monitoring, redundancy and on-call cover.

Frequently asked questions

How do you calculate the cost of downtime?

Add three things: revenue you lose while the service is unavailable, the wage cost of staff who cannot work, and one-off recovery costs like overtime or vendor call-outs. Revenue lost = revenue per hour × hours of downtime × the share of that revenue you do not recover later.

What is a typical cost of downtime per minute?

It varies enormously by company size and how directly the outage hits sales. A small online shop might lose a few dollars a minute; a large e-commerce or trading platform can lose thousands. That is exactly why this calculator asks for your own numbers instead of quoting an average.

Should I count reputational damage and customer churn?

They are real but hard to put a number on reliably, so this calculator leaves them out. Treat its total as a floor. For a major outage, add a separate estimate for customers who leave and do not come back.

What does "revenue you actually lose" mean?

If a customer cannot buy during the outage but comes back an hour later and buys anyway, that sale was delayed, not lost. Set the "share of revenue actually lost" below 100% to reflect sales you recover through other channels or later.

Why show cost per minute?

A per-minute figure makes the trade-off concrete when deciding how much to spend on redundancy, monitoring and faster recovery. "This change shaves 20 minutes off recovery" turns into a money number.