Find the right backup power setup before you overspend.
Use free calculators, setup guides, and comparison tools to estimate battery runtime, size your power station, and understand what gear you actually need.
- Free calculators
- No fake reviews
- Estimate before you buy
- Built for outages, travel, remote work, and backup internet
Free estimation tools
Run the numbers first
Backup power is just math: watts, hours, and watt-hours. These tools do the math with honest assumptions, so the size you buy matches the outage you're planning for.
Battery Runtime Calculator
Best for: Answering "how long will this battery run my device?" before you buy it.
CalculatorPower Station Sizing Calculator
Best for: Turning device watts and desired hours into the capacity you should shop for.
CalculatorSolar Recharge Calculator
Best for: Checking whether a solar panel can realistically refill your battery each day.
Decision wizardGear Finder
Best for: Getting a full setup suggestion from six quick questions — no specs knowledge needed.
Start from your situation
What are you trying to keep running?
Pick the scenario closest to yours and the Gear Finder pre-loads it — typical wattage, a sensible capacity class, and what to verify before buying.
Router & modem backup
Keep home internet up during an outage
Under 300WhLaptop through a full workday
Power a laptop for 8+ hours during an outage or away from outlets
500–1,000WhBackup internet (satellite or hotspot)
Keep a backup internet connection online when home service or power fails
500–1,000WhApartment outage kit
Ride out a multi-hour outage in an apartment: lights, phones, internet, and a fan
1,000–2,000WhWeekend camping power
Run lights, phones, and small electronics at a campsite for a weekend
500–1,000WhBudget emergency basics
Cover phones, lights, and internet in an outage without overspending
500–1,000WhSmall fridge backup
Keep a mini fridge or compact refrigerator cold through an outage
500–1,000WhRemote work anywhere
Power a laptop, monitor, hotspot, and accessories away from reliable outlets
1,000–2,000WhCapacity badges show the class we'd suggest for a standard 8–12 hour target. Shorter or longer outages shift the math — the Gear Finder adjusts it for you.
Featured comparison
Power station vs UPS vs power bank
Most backup-power overspending starts with buying the wrong category, not the wrong model. Here's how the three options actually differ — in honest, generic ranges.
Some links on this page may be paid links. If you buy through them, Cynosure LLC may earn a commission at no extra cost to you. We do not claim to have personally tested products unless clearly stated.
| Feature | Portable power station | UPS (battery backup) | USB power bank |
|---|---|---|---|
| Best for | Longer outages, camping, and off-grid work | Instant switchover for desk and network gear | Phones, tablets, and small USB devices |
| Capacity | 300Wh to 2,000Wh+ depending on class | Small — often roughly 300–500Wh equivalent | ~90Wh for a typical 25,000mAh bank |
| AC output | Yes — inverters from ~300W to 2,000W+ | Yes — a few outlets, sized for short bridging | Usually none — USB ports only |
| Runtime for a router (~15W) | A 300Wh model: roughly 20+ hours | Typically ~1–3 hours | Most can't power a router directly — phones only |
| Portability | Luggable — roughly 7–50 lb by class | Meant to stay put; heavy for its capacity | Fits in a bag or a pocket |
| Typical cost | $150–$2,000+ by capacity | $60–$200 | $20–$80 |
Ranges are honest category estimates, not measurements of specific products. Always verify manufacturer specs.
Get the free Emergency Power Planning Checklist
A practical, no-hype checklist for planning outage power: what to size, what to verify, and what to skip.
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Learn before you spend
Latest buying guides
Plain-English guides on sizing, comparing, and avoiding the usual backup-power mistakes — with the math shown, not hidden.
Backup Internet Power Planning: A Complete Walkthrough
A step-by-step plan for backup internet power: inventory your gear, budget watts for primary and fallback paths, and build tiered 2-hour to multi-day plans.
Backup internetBackup Power for Satellite Internet Terminals
How to size backup power for a satellite internet terminal: realistic wattage, evening vs all-day sizing math, DC-direct options, and pairing with solar.
Budget setupsBudget Backup Power: A Sensible Setup When Money Is Tight
A sensible order for building backup power when money is tight: phones first, then internet, then comfort — plus the red flags to avoid on cheap gear.
Travel & remote workCamping Power Setup for Beginners
A beginner's camping power plan: a weekend watt-hour budget, why smaller usually wins, solar realism at camp, 12V-first habits, and safe charging.
Beginner basicsHow to Choose a Portable Power Station Without Overspending
Size a portable power station from your real loads, learn which specs actually matter, and use a price-per-watt-hour check to avoid overspending.
Backup internetKeeping Your Router and Modem Alive During a Power Outage
What it takes to keep your router and modem online in an outage: whether your internet survives, UPS switchover, sizing, placement, and how to test it.
How Power Preflight works
Estimate. Compare. Buy once.
We publish our formulas and assumptions, we don't write fake reviews, and we'd rather you buy the right size than the biggest one.
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Estimate
Add up your real device watts, then use the free calculators to turn them into runtime and capacity numbers.
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Compare
Put capacity classes and setup types side by side so the trade-offs are clear before you shop.
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Buy once
Verify the specs that matter and buy the size you actually need — nothing bigger. Our methodology is public.
Calculations are estimates. Verify manufacturer specs. Some links may earn commissions.