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What size power station do you need to run a fridge and chest freezer for 48 hours?

Short answer: 7,115 Wh of rated capacity — that's the 4 kWh+ — expandable system or generator territory. A weekend outage with both cold appliances protected.

The math, appliance by appliance

ApplianceAvg drawHours usedEnergy
Refrigerator (full-size)60 W48 h2,880 Wh
Chest freezer45 W48 h2,160 Wh
Energy needed over 48 hours5,040 Wh
÷ 0.85 inverter efficiency5,929 Wh
× 1.2 headroom (ageing, cold, overrun)7,115 Wh
Recommended: 4 kWh+ — expandable system or generator territory. Output check: 270 W continuous, 1,020 W surge.

Fridges and freezers use their average cycling draw for energy and full compressor draw for the output check — that's why the numbers differ from the label.

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Quick answers

Can a smaller unit than 7,115 Wh work?
The bare energy need is 5,929 Wh after inverter losses; the extra 20% covers battery ageing, cold weather, and outages running long. A smaller unit works on a good day — this size works on a bad one.
What about output watts, not just capacity?
The station must sustain 270 W continuous and survive a 1,020 W start-up surge. Nearly every unit in the 4 kWh+ clears both comfortably.
Could solar keep this running indefinitely?
Roughly 840 W of panels replaces a day's usage with ~4 hours of decent sun at real-world (75%) efficiency. Half that solar doubles your runtime instead of sustaining it.