Use this page to check electric string trimmer electricity consumption for your own electric string trimmer: enter your wattage, hours of use per day and electricity rate, and press Calculate. You see your daily, monthly and yearly cost plus your yearly kWh consumption. Those same results also cover electric string trimmer power consumption. Also see how many watts does an engine heater use.
Wondering what your yard tools add to the bill? Your electric string trimmer electricity consumption comes down to three numbers: the motor's wattage, the hours you run it and the rate your utility charges, and together they show that a typical homeowner pays only about $12 a year to keep the edges tidy. This guide turns each number into kilowatt-hours and dollars so you can price your own power draw in seconds.
An electric string trimmer is one of the lightest electrical loads in a garage. Its small motor spins a length of trimmer line and rarely runs for more than an hour at a time, so the energy consumption per session is tiny compared with a dryer, an air conditioner or even a lawn mower. Still, the figure is worth knowing, because it lets you compare a corded model, a cordless model and a gas trimmer on a like-for-like basis.
The utility bills in kilowatt-hours (kWh), so every estimate ends up there. One kWh is the energy used by a 1,000-watt load running for one hour. A trimmer rated at 525 watts therefore uses 0.525 kWh for every hour of cutting, and that single number is the starting point for every calculation that follows.
Wattage is the rate at which the motor draws power at any moment. Watt-hours measure how much energy was used over time, and dividing by 1,000 converts them into kWh. If a label lists only amps, multiply the amps by the household voltage of 120 V to approximate the wattage; a 4.4 A trimmer therefore draws roughly 525 W.
The same arithmetic works backward. A battery pack that stores 108 watt hours holds 0.108 kWh, which is why a cordless tool's cost is really the price of recharging it.
Every motor draws more for a split second when it spins up. This startup surge is why spec tables list both starting wattage and running wattage. For a household estimate, ignore the surge: it lasts a fraction of a second and adds almost nothing to your kWh total. Use the running figure for cost, and keep the starting figure in mind only when you are sizing a generator or extension cord.
The method is the same for any appliance, and it is also how you go from watts to kWh for any tool you own. Start from the nameplate wattage, convert to kilowatts, multiply by the hours of use, then multiply by your electricity rate. Written as a formula, it looks like this:
$$\text{Energy (kWh)} = \frac{\text{Watts} \times \text{Hours}}{1000}$$
$$\text{Cost} = \text{Energy (kWh)} \times \text{Rate per kWh}$$
Use the average rate printed on your latest statement rather than a guess, because the price per kWh changes more from state to state than the trimmer's wattage ever will. When you only know the national average, treat the result as a ballpark.
Take a corded trimmer rated at 525 W. You cut for 0.75 hours (45 minutes) per session, three sessions a week, and your electricity rate is $0.198 per kWh. Here is how the figures build up:
$$\frac{525 \times 0.75}{1000} = 0.39 \text{ kWh per session}$$
Three sessions give 2.25 hours a week, or 117 hours across 52 weeks, so the yearly energy is \(0.525 \times 117 = 61.43\) kWh. At $0.198 per kWh, that costs $12.16 a year.
The table below breaks the same example into the periods most people ask about. The cost per hour is just 0.525 kWh times $0.198, and every other row scales from it.
| Period | Energy (kWh) | Cost |
|---|---|---|
| Per hour | 0.525 | $0.10 |
| Per session (45 minutes) | 0.39 | $0.08 |
| Per day (averaged over the year) | 0.17 | $0.03 |
| Per week (2.25 hours) | 1.18 | $0.23 |
| Per month | 5.12 | $1.01 |
| Per year (117 hours) | 61.43 | $12.16 |
Spread over a full calendar, the daily energy use averages only 0.17 kWh, a few cents a day. The monthly cost of $1.01 and the yearly cost of $12.16 are the numbers to compare with other appliances.
Two inputs change the answer the most: how many watts the motor pulls and what a kWh costs where you live. The first table keeps the usage at 117 hours a year and the rate at $0.198, then varies only the wattage, from a light weed eater to a heavy-duty model.
| Trimmer type | Wattage | kWh per year | Cost per year |
|---|---|---|---|
| Light corded | 360 W | 42.12 | $8.34 |
| Mid-range corded | 450 W | 52.65 | $10.42 |
| Example model | 525 W | 61.43 | $12.16 |
| Long-reach corded | 650 W | 76.05 | $15.06 |
| Heavy-duty edger | 1,000 W | 117.00 | $23.17 |
Now hold the 525 W motor steady and change the rate. Local pricing swings widely, which is why the same weed trimmer can cost twice as much in one state as in another.
| Rate per kWh | Cost per year |
|---|---|
| $0.110 | $6.76 |
| $0.150 | $9.21 |
| $0.198 | $12.16 |
| $0.280 | $17.20 |
| $0.380 | $23.34 |
Hours matter as much as either input. At the same wattage and rate, 5 hours a week uses 136.5 kWh and costs $27.03 a year, while 10 hours a week uses 273.0 kWh and costs $54.05.
A corded model draws its wattage straight from the wall, so the estimate above applies directly. A cordless model is different: the motor takes energy from a battery, and what you pay for is the electricity the charger pulls to refill it. That is why the useful numbers are voltage and amp-hours rather than a single fixed wattage.
Multiply the pack voltage by its amp-hours to get watt hours. A 36 V pack rated at 3.0 Ah stores 108 Wh. Chargers lose some energy as heat, so assume about 12% loss and divide by 0.88: the wall draw is roughly 123 Wh, or 0.123 kWh, which costs about 2.4 cents per charge at $0.198 per kWh.
That is lower than the corded example, which makes the battery trimmer the cheaper tool to run, even though the pack is the more expensive part to buy.
If the nearest outlet is out of reach, a portable power station or small generator can feed a corded trimmer. A 525 W trimmer running for 0.75 hours draws about 0.39 kWh, so a 600 W unit with a few hundred usable watt-hours covers a session or two; leave a safety margin on the continuous AC rating. A cordless owner rarely needs this setup, because the power station is more often used to recharge the pack, and extra capacity there only adds runtime for the charger.
Yard owners often run both tools in the same session, so it helps to see how an electric hedge trimmer compares. Hedge tools usually list their amperage on the label, which makes the 120 V shortcut easy to apply, and the chart below shows the typical spread against the electric grass trimmer class.
| Tool | Typical label | Approximate wattage |
|---|---|---|
| Small corded hedge trimmer | 3.0 A | 360 W |
| Standard corded hedge trimmer | 3.8 A | 456 W |
| Electric grass trimmer, corded | 4.4 A | 525 W |
| Long-reach hedge trimmer | 4.5 A | 540 W |
A hedge trimmer therefore lands in the same band as a string trimmer, and its yearly cost scales with your hours in exactly the same way: a 456 W model run for the same 117 hours uses 53.35 kWh and costs about $10.56, against $12.16 for the 525 W string trimmer.
Because the cost is already small, the aim here is not dramatic savings but the habit of using less power per square foot of lawn. These steps reduce the energy bill without changing how clean the edge looks:
Each habit is an energy saving measured in cents, but together they keep the figure at the low end of the ranges in the tables above.
Cost per kWh favors electric on almost any property, but runtime does not. A cordless pack may run out before a big yard is finished, and a corded trimmer is limited by the length of the cord. On an acre or more, owners often switch to a gas trimmer for reach and stamina, accepting a higher operating cost per hour. For a typical suburban lawn with a few hundred feet of edging, the electric model remains the more cost-effective choice for household use, and the quiet motor is a bonus. Related: how much electricity does a pedestal fan use.
When you compare options, use spec sheets for wattage or voltage, then run the same formula for each. A homeowner who owns a lawn mower, a hedge trimmer and a string trimmer can add the three yearly kWh figures together to see the full cost of yard care; the string trimmer will almost always be the smallest line item.
Marisol Quintero in Dayton, Ohio, edges a 0.28-acre corner lot and wants to estimate her trimmer's electricity consumption and see whether a $9 monthly budget line for yard electricity is overkill. Her corded trimmer's plate reads 4.7 A on a 120 V circuit, so she multiplies 4.7 × 120 and enters 564 W. Her statement shows $0.1623 per kWh, and over 26 weeks of growing season she trims 2.5 hours a week, which makes 65 hours. Also see how many watts does an elliptical machine use.
The electric trimmer energy use calculator multiplies 0.564 kW by 65 hours and returns 36.66 kWh, then multiplies by her rate to show a seasonal cost of $5.95. That is about 50 cents a week of electricity for the whole season, so the trimmer is not the line item to worry about on her bill.
She then reruns it with the hours changed to 4.0 a week to test the heavy-growth weeks in June: 58.6 kWh and $9.51, still tiny. With the answer in hand she lowers the budget line to $6 and keeps the trimmer on the same plug. This is how the electric string trimmer electricity cost figure becomes a decision.