At 120 volts, the voltage household extension cords are made for in the US, 1,500 watts draws 12.5 amps, which is 1,500 divided by 120.
Convert to
W
A
V
Read the watts, and the volts if they aren’t 120, from the device’s nameplate. To add up several things on one cord, type a sum such as 600 + 300 + 60.
The answer
12.5amps
1,500 W ÷ 120 V = 12.5 A. Amps are the watts divided by the volts.
The nameplate is the label with the device’s ratings.
Compare amps with an extension cord’s rating in amps, or watts with its rating in watts.
1,500 watts at other voltages
The amps 1,500 watts draws at each voltage
Volts
Amps
110 V
13.64 A
115 V
13.04 A
120 V
12.5 A
125 V
12 A
230 V
6.52 A
240 V
6.25 A
1,500 divided by the volts, rounded to two decimal places. Use the volts on the device’s nameplate.
What draws 1,500 watts
Most of Lasko’s space heaters list 1,500 watts. Whatever the device, its watts are printed on its label or nameplate.
A heater that size goes straight into a wall outlet, never an extension cord or a power strip. Plug nothing else into that outlet, since that can overload the circuit. Lasko’s model 106 manual also says not to plug other devices into the same outlet or circuit as the heater. See space heaters and extension cords, and for the running cost, what a space heater costs to run.
1,500 watts on an extension cord
For something other than a heater, 12.5 amps is just under the 13 amps Southwire rates its 16 gauge cords for up to 50 feet, and over the 10 amps it gives them at 100 feet. Read the tag on your cord, and see the gauge for 12.5 amps by length, from four makers’ charts.
What a circuit in your home can carry depends on its wiring and breaker. Ask an electrician before adding a big load to one.
Common questions
How many amps is 1,000 or 2,000 watts?
At 120 volts, 1,000 watts is 8.33 amps and 2,000 watts is 16.67 amps. Divide the watts by the volts.
Is 1,500 watts too much for one outlet?
For a space heater, keep the outlet to the heater alone, because anything else in the same outlet can overload the circuit. For other things, follow the device's manual, and ask an electrician about the circuit.
The household voltage and the space heater advice come from the CPSC and the NFPA, the heater wattage and outlet warning from Lasko, and the cord ratings from Southwire. Checked against published data from Southwire, CPSC, Lasko and NFPA.
See all 7 sources
Southwire, Cord Solutions Catalog: decoding jacket types, amp ratings of its 16, 14, 12 and 10 gauge extension cords at 25, 50 and 100 ft, and generator cables and voltage drop
US Consumer Product Safety Commission, “Keep Warm and Safe This Winter” (January 2026): space heaters directly into a wall outlet, three feet, off when sleeping; portable generators at least 20 feet from the home
National Fire Protection Association, Educational Messages Desk Reference (2026 edition): space heaters, wall outlets and plugs
Lasko, MyHeat personal heater model 106 instructions (on Lasko's own help center)
US Consumer Product Safety Commission, ballot vote sheet and staff package, extension cord proposed rule (January 2015): household current at nominal 120 volts AC, and UL 817's jacketed cord for outdoor extension cords
Southwire product pages: 16/3 SJTW 15 ft (2306SW8808) and 16/3 SJOW 10 ft (2211SW8808) outdoor extension cords, 13 A, 125 V, 1625 W; 10/3 SJTW 50 ft with a NEMA 5-15P plug (2688SW0002), 15 A, 125 V, 1875 W
Lasko product pages (lasko.com): the 9 in. ceramic tabletop heater 754200 (1500 W high, 900 W low), the Ellipse 12 in. ceramic heater CD12950 (Auto Eco mode), and its other heaters' wattage
General guidance from manufacturer and standards data. Products vary, so check the label and the maker's instructions.