System Availability Calculator
Explore component repair time, required working nodes and active redundancy using an independent-node availability model.
Your app workspace
- MTBF/MTTR inputs and up to 200 installed nodes
- Exact binomial model for tolerated simultaneous failures
- Annual uptime, downtime and availability nines
- Series/parallel comparisons, named projects and printable results
Designed for a browser on iPhone, iPad, Android and desktop. Add it to your Home Screen and prepare its files for offline use. Local work is stored on the device you use.
Actual Web App preview. Your inputs, projects or progress are saved in your own workspace on this device.
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$1.99
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Learning and planning tools for educational use.
About this Web App
What does System Availability Calculator include, and what changed from the native source?
Explore component repair time, required working nodes and active redundancy using an independent-node availability model. The Web App improves the older approximate formula with a full independent-node binomial model, explicit MTBF hours and 8,760 annual hours. It is a planning model and does not account for common-cause failures or imperfect switching.