Uptime & Downtime Calculator

How to use the Uptime Calculator.

Using our calculator is simple:

1. Enter your uptime percentage – Most services aim for 99% uptime or higher. Enter the percentage you want to analyze.
2. Select your time frame – Choose whether you want to calculate downtime for a day, week, month, or year.
3. Get instant results – The tool will show you how much downtime corresponds to your uptime percentage.

For example, if your service has 99.9% uptime, that means 8 hours and 45 minutes of downtime per year. Want to know the impact of increasing your uptime to 99.99%? Simply adjust the input and see the difference.

What is an optimal amount of uptime?

The ideal uptime percentage depends on the needs of your business and your customers' expectations. While 100% uptime is unrealistic, the goal is to minimize downtime to a level where it does not significantly disrupt operations or impact users.

For most businesses, the following uptime percentages serve as benchmarks:

• 99.9% uptime ("three nines") – Suitable for general web hosting, SaaS platforms, and e-commerce businesses where occasional downtime is acceptable.
• 99.99% uptime ("four nines") – A better target for financial institutions, healthcare systems, and critical online services that require higher reliability.
• 99.999% uptime ("five nines") – The gold standard for mission-critical applications like telecom services and data centers, where even seconds of downtime can have major consequences.

An optimal uptime level is one that balances cost and performance while ensuring an uninterrupted experience for users. If downtime leads to lost revenue or safety risks, a higher uptime target is necessary.