Keep the lights on for what matters.

Clear, engineering-grade answers about UPS systems, battery backup and power protection. Size it right, set it up properly, and know exactly what to do when it beeps.

Find the right UPS size Fix a UPS problem

Start with your situation

Most people arrive with one of these questions. Each path leads to the guide and tool that answers it fastest.

What size UPS do I need?Real watts, headroom and runtime in four steps Which UPS should I buy?A checklist that avoids the common traps Why is my UPS beeping?Decode the sound, then fix the cause Is my battery done?Tests, signs and the replacement point Keep the internet upHours of runtime for very little money Protect a NAS or homelabGraceful shutdown that actually works UPS for a gaming PCTransient spikes, PFC and pure sine UPS or surge protector?What each one does and does not stop

Explore the topics

From first principles to rack-room detail, organized the way you actually work through a backup power decision.

UPS Fundamentals

How a UPS works, the three topologies, and how to read a spec sheet.

Sizing & Runtime

Turn your equipment list into the right capacity and a realistic runtime.

UPS Batteries

Chemistry, lifespan, replacement and safe disposal.

Power Quality & Surge Protection

Surges, sags, brownouts and noise, and the right defense for each.

Use Cases

Device-by-device advice, including when a UPS is the wrong tool.

Troubleshooting & Alarms

Diagnostic flows for beeps, lights and failures, safest checks first.

Installation & Maintenance

Setup, placement, generators and a maintenance routine that prevents surprises.

Software & Monitoring

Automatic shutdown and monitoring for Windows, macOS, Linux and NAS.

Comparisons & Brands

Balanced head-to-heads and orientation guides to the major product lines.

Calculators that show their work

Every tool explains its assumptions, models real battery behavior, and runs entirely in your browser.

ToolUPS Sizing CalculatorBuild your load from real device data and get a recommended class, waveform and topology. ToolUPS Runtime CalculatorRuntime at any load, with lead-acid rate effects, battery health and a runtime curve. ToolBattery Life EstimatorHow heat and outages shorten battery life, and when to plan replacement. ToolUPS Alarm DecoderMatch the beep to its most likely cause and the next step. DataDevice Power Draw DatabaseTypical and peak watts for common equipment, with a verdict on UPS suitability. ToolVA to Watts ConverterTurn the big number on the box into the one that matters.

How we work

Mechanism first

We explain why things happen, from Peukert losses to transfer times, so advice holds up when your situation differs from the example.

Numbers you can check

Worked examples show the arithmetic. Typical figures are given as honest ranges, with sources and our assumptions stated.

Safety without drama

We say plainly when a UPS is the wrong tool, when a battery is dangerous, and when work belongs to a licensed electrician.

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