BLUETTI EB3A
Twice the inverter of its size class, but the shortest warranty here.
- Capacity
- 268 Wh
- AC output
- 600 W
- Chemistry
- LiFePO4
- Fridge-days
- ≈ 0.6
$299 MSRP
Read the review →
Sizing calculator
What Size Portable Power Station Do I Need?
Add the devices you actually run, and we'll show the watt-hour math — then the stations that clear it.
- No email required
- Manufacturer specs
- Math shown, not hidden
1
Add Your Devices
Add the devices you plan to power.
DeviceWattsQuantityRun time
2
Usage Scenario (Optional)
Helps refine your recommendation.
3
System Efficiency
Power stations lose energy to inverter & battery losses.
85%
Your Estimated Power Needs
Total daily use
0 Wh
Days
2.5
Efficiency
85%
Estimated Total Capacity Needed
0 Wh
Recommended Battery Size
Best Fit—
Includes 20–30% headroom for real-world use.
What size power station do I need? A worked example
The calculator above does this for your own devices. Here is the same arithmetic, in full, for a typical van-life kit — so you can check the method before you trust the tool.
| Device | Watts | Qty | Hours/day | Wh/day |
|---|---|---|---|---|
| 12V fridge | 25 | 1 | 24 | 600 |
| CPAP (no humidifier) | 40 | 1 | 8 | 320 |
| Phones | 10 | 2 | 8 | 160 |
| LED lights | 5 | 2 | 10 | 100 |
| Daily total | 1,180 | |||
1,180 Wh/day ÷ 85% inverter efficiency = 1,388 Wh
Add 25% headroom and round to the nearest 100 Wh.
Capacity to buy
1,400 – 1,700 Wh
That straddles the Medium and Large tiers below, so shop the 1,500–2,000 Wh range — enough for a fridge, a CPAP and charging for a night without recharging. The full method, including how to handle compressor duty cycles and startup surge, is in the sizing guide.
Recommended Power Stations
Matches update as you change the calculator. Prices shown are MSRP — street prices are usually lower.
EcoFlow RIVER 3 Plus
The only sub-300 Wh unit that expands — to 858 Wh with an extra battery.
- Capacity
- 286 Wh
- AC output
- 600 W
- Chemistry
- LiFePO4
- Fridge-days
- ≈ 0.6
$299 MSRP Review pending
Jackery Explorer 300 Plus
Compact device-charging workhorse for tent trips.
- Capacity
- 288 Wh
- AC output
- 300 W
- Chemistry
- LiFePO4
- Fridge-days
- ≈ 0.6
$299 MSRP
Read the review →
Jackery Explorer 600 v2
The lightest 640 Wh unit made, and the bridge between weekend batteries and the 1 kWh class.
- Capacity
- 640 Wh
- AC output
- 500 W
- Chemistry
- LiFePO4
- Fridge-days
- ≈ 1.4
$429 MSRP Review pending
Wattage Tier Guide
| Tier | Capacity (Wh) | Best for | Example use |
|---|---|---|---|
| Small | 100 – 500 Wh | Phones, lights, small devices | Day trips, emergencies |
| Medium | 500 – 1,500 Wh | Camping, laptops, small appliances | Weekend trips, van life |
| Large | 1,500 – 3,000 Wh | Mini fridges, power tools, CPAP | Extended camping, RV |
| Extra Large | 3,000+ Wh | High-demand appliances, whole RV | Off-grid living, long term |
Pro Tips
- Add 20–30% extra capacity for unexpected usage.
- Fridges have high startup wattage — size accordingly.
- Solar charging can extend your runtime significantly.
- Check your device's label for accurate wattage.
How Sizing Works
- 1 Add your devices and their wattage.
- 2 Set how long you'll run each device daily.
- 3 We calculate total watt-hours needed.
- 4 Get the right battery size recommendation.
Common Appliance Runtimes (1,000 Wh)
- Laptop (60W) ~12 – 16 hrs
- Mini fridge (60W avg.) ~14 – 18 hrs
- CPAP machine (40W) ~18 – 22 hrs
- LED light (5W) ~80 – 100 hrs
Frequently Asked Questions
How do I calculate watt-hours?
Watt-hours = watts × hours. A 60 W laptop used 4 hours a day burns 240 Wh. Add every device's number together for your total daily use.
What's the difference between Wh and W?
Watts (W) measure instantaneous power draw; watt-hours (Wh) measure energy over time. A power station's capacity is in Wh; its inverter limit is in W. You need both to fit: enough Wh to last, enough W to run your biggest device.
How much extra capacity should I add?
Add 20–30% over your calculated need. It covers inverter losses, battery aging, cold-weather derating, and the loads you forgot to list.
Do power stations lose energy?
Yes — converting DC battery power to AC through the inverter typically loses 10–15%. That's why the calculator applies an efficiency factor instead of assuming the rated capacity is fully usable.