From operating inputs to a reviewable result.
The path stays open at every step.
- 01
Operating inputs
Load, configuration, and site conditions
- 02
Formula & source
Method and reference shown beside the result
- 03
Assumptions
Limits remain part of the readout
The toolkit / 03 disciplines
Three everyday planning questions. One clear method.
Built for engineers, facility managers, technicians, MEP consultants, and students who want to inspect the reasoning—not just copy a number.
Browse all calculators- 01
UPS battery runtime
Estimate runtime from load, battery-bank configuration, UPS efficiency, and remaining capacity.
LOAD · BANK CONFIGURATION · EFFICIENCY · REMAINING CAPACITY
- 02
Cooling load & BTU
Build a cooling-load estimate from IT demand, lighting, people, and the building envelope.
IT LOAD · LIGHTING · PEOPLE · ENVELOPE
- 03
Rack power & PDU capacity
Plan rack power density and evaluate PDU capacity around the intended load.
RACK DENSITY · POWER · PDU CAPACITY
A result you can review
No black-box numbers.
Each calculation keeps its working in frame, so a planning estimate can be understood in context and checked against the source information that matters to your facility.
- 01 / TRACE
Inputs
The values and conditions behind the estimate stay visible.
- 02 / TRACE
Formula + source
See how the calculation is formed and where its method comes from.
- 03 / TRACE
Assumptions
Review the limits and assumptions before using the result for planning.
Every result is an estimate for planning only—not a substitute for a licensed engineer’s design or manufacturer data.
Individual or team
Calculate freely. Keep the work when you need to.
Every calculator is free for individual, unsaved use. Paid plans add the tools to retain work, share it, and bring it into project records.
Included with paid plans
- Saved projects
- Branded PDF reports
- CSV exports
- Calculation history
- Shared team workspaces
Need a shared workspace for your team? Get in touch to discuss the right fit.
Contact LoadCairn