Most slow cookers use about 70 to 250 watts on Low and about 150 to 350 watts on High on average once warmed up (even if the nameplate rating is higher). For inverter/generator planning, it’s still smart to allow 200 to 600 watts of headroom depending on size.
For full system planning, use the WattSizing Calculator.
Quick Answer
Most slow cookers use about 70 to 250 watts on Low and about 150 to 350 watts on High on average once warmed up. For inverter/generator planning, it’s smart to allow 200 to 600 watts of available headroom depending on size.
Detailed Explanation
A slow cooker is a thermostatically controlled heating load. It often pulls more power during the warm-up phase, then cycles on and off to maintain temperature. That’s why many people see average watt draw lower than the maximum rating printed on the label.
Energy use depends on three things:
- How long you cook (4–10 hours is common)
- Whether you use Low/High/Keep Warm
- How full the pot is and how cold the ingredients are at the start
Watt Table
| Slow Cooker Size / Type | Typical Running Watts (Warm-Up / Peak) | Typical Average Watts (After Warm-Up) |
|---|---|---|
| Small (1.5–3 qt) | 120 - 200 W | 70 - 140 W |
| Medium (4–6 qt) | 180 - 320 W | 110 - 220 W |
| Large (7–8 qt) | 250 - 400 W | 150 - 280 W |
| Multi-cooker “slow cook mode” | 200 - 500 W | 120 - 300 W |
Calculation Example
Example: A 6-qt slow cooker averages 180 W during a 7-hour cook.
- kWh = (180 x 7) / 1000 = 1.26 kWh
- At $0.16/kWh, cost is about $0.20 per cook
- If you run it 12 times/month, that’s about $2.42/month
For off-grid or backup planning, start with How to Calculate Daily Energy Use and then check inverter guidance in Inverter Sizing for Off-Grid Solar.
Tips to Reduce Power Usage
- Use Low once preheated if your recipe allows; High can increase average watts.
- Keep the lid on (every peek can dump heat and extend runtime).
- Thaw ingredients safely first; starting with frozen food can lengthen warm-up time.
- Avoid running other high-watt appliances simultaneously on small backup systems.
FAQs
Does a slow cooker have startup surge?
Not like a motor or compressor. It may draw higher watts during the initial warm-up, but it’s still a heating load without a big surge spike.
Why does my meter show the wattage going up and down?
That’s normal thermostat cycling. The cooker switches the heating element on and off to hold temperature.
Is a slow cooker efficient compared to an oven?
Often yes for long, low-temperature cooking because it’s insulated and uses lower steady watts. For a direct comparison, see How Many Watts Does an Electric Oven Use and How Many Watts Does an Induction Cooktop Use.
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