---
product_id: 1325926
title: "P3 P4400 Kill A Watt Electricity Usage Monitor"
price: "$70.24"
currency: USD
in_stock: true
reviews_count: 8
url: https://www.desertcart.us/products/1325926-p3-p4400-kill-a-watt-electricity-usage-monitor
store_origin: US
region: United States of America
---

# 115V AC compatibility 4 time-frame usage tracking 0.2-2.0% measurement accuracy P3 P4400 Kill A Watt Electricity Usage Monitor

**Price:** $70.24
**Availability:** ✅ In Stock

## Summary

> ⚡ Power your savings with precision and style!

## Quick Answers

- **What is this?** P3 P4400 Kill A Watt Electricity Usage Monitor
- **How much does it cost?** $70.24 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/1325926-p3-p4400-kill-a-watt-electricity-usage-monitor)

## Best For

- Customers looking for quality international products

## Why This Product

- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Large, Clear LCD Display:** Easily read real-time energy stats without squinting or guesswork.
- • **Portable & User-Friendly:** Compact design lets you track energy use anywhere, empowering smarter, eco-conscious choices.
- • **Precision Power Tracking:** Monitor volts, amps, and wattage with up to 0.2% accuracy for data-driven energy decisions.
- • **Multi-Period Usage Insights:** Analyze your electricity consumption by day, week, month, or year to optimize your bills.
- • **Universal Appliance Compatibility:** Works seamlessly with 115V AC appliances and inverters for versatile monitoring.

## Overview

The P4400 Kill A Watt Electricity Usage Monitor is a portable, highly accurate device that measures electrical consumption of 115V AC appliances. Featuring a large LCD display and four selectable time frames (day, week, month, year), it provides detailed insights into volts, amps, and wattage with 0.2-2.0% accuracy. Ideal for professionals seeking to optimize energy efficiency and reduce costs, it supports inverter compatibility and requires minimal setup.

## Description

desertcart.com Empowers You to Save Hundreds on Electric Bills Electricity bills are rising. Now you can cut down on costs and find out what appliances are actually worth keeping plugged in. Simply connect these appliances to the Kill A Watt, and it will assess how efficient they really are. The large LCD display counts consumption by the kilowatt-hour, the same as your local utility. You can calculate your electrical expenses by the day, week, month, even an entire year. Also check the quality of your power by monitoring voltage, line frequency, and power factor. Now you will know if it is time for a new refrigerator or if that old air conditioner is still saving you money. Kill A Watt can help you reduce your power bill and will help find power-wasting appliances so you are able to decide whether it is worth keeping them plugged in. For standard 115 VAC appliances only, 15 amps maximum, 125 VAC maximum. Find Out How Much Electricity You're Using The U.S Department of Energy reports that 20% of our electric bills come from items that are left plugged in when they are not in use, or items that are in standby mode. With the Kill A Watt P4400 we can monitor the energy eaters in our homes and cut down our electric bills at the same time. Plug whatever item you want into the device and it will tell you the efficiency of that item by displaying the kilowatt per hour. This device will help you determine which items are costing you the most to run. The Kill A Watt also calculates voltage, line frequency, current, and power factor. You can calculate your electric bill before you even receive it from the electric company. Test The Quality of Your Home's Power But measuring appliance consumption is just the tip of the iceberg. Because it can monitor voltage (Volt) and line frequency it can also test if an outlet is working, or evaluate the quality of the electrical power provided by your utility company. It can detect voltage drops around the house, help to predict brownout conditions or to make sure a new home's outlets are in working condition before escrow closes. About P3 International Founded in 1987, P3 International is a privately owned manufacturer of solution oriented consumer products. For the last twenty years they have strived to develop products that are easy to use and ahead of their time. Thanks to their customer-centric attitude and support from their clients, they have experienced steady growth over the past decade. They are committed to manufacturing high quality products that appeal to a variety of different people, from the environmentally conscious to the more technologically-minded consumer. With this philosophy driving them they are always looking for innovative new products which they can offer their customers. Their unique products have garnered much attention, in particular the Kill A Watt. Reviews of P3 products have been featured in newspapers such as The New York Times and The Wall Street Journal. Technical SpecificationsAccuracy: +/- 0.2% Input Power: 115 volts AC, 60 Hz Max Current: 15 amps Max Voltage: 125 volts Max Power: 1875 VA Dimensions: 5.1 inches long x 1.6 inches thick x 2.4 inches wide Approvals: ETL (c), ETL (us) Origin: China Manufacturer Warranty: 6 months

Review: Accurate, Simple, and Addictively Useful - Accurate, Simple, and Addictively Useful The P3 Kill A Watt Electricity Usage Monitor is one of those inexpensive gadgets that quietly changes how you think about energy use. I first bought it to see how much power my old refrigerator was pulling—and ended up testing every appliance in the house. Setup is instant: plug it into the wall, connect any device, and the bright LCD display immediately shows volts, amps, and watts in real time. Leave it running for hours or days, and it totals up the kilowatt-hours (kWh), letting you see exactly what that appliance costs you per day or month. What makes it so helpful is how accurate and intuitive it is. You don’t need to be an engineer—just read the wattage and multiply by your utility rate. I found a few “phantom” power hogs drawing 10–20 watts even when off (like a cable box and an older UPS). It’s also great for testing PC builds, aquarium setups, or any electronics to ensure your power supply is sufficient. The build quality is solid, and the display remains easy to read even after years of use. The only caution: it’s designed for 115V North American outlets only—not for international use. Bottom line: A must-have tool for anyone curious about energy use or looking to cut electric bills. Simple, accurate, and surprisingly enlightening—it pays for itself quickly.
Review: Works as intended. - Works great helped estimate electrical usage on a few big appliances.

## Features

- Choose from the Kill-a-Watt's four settings to monitor your electrical usage
- Monitor your electrical usage by day, week, month, or year
- Features easy-to-read screen
- Electricity usage monitor connects to appliances and assesses efficiency
- Large LCD display counts consumption by the kilowatt-hour
- Calculates electricity expenses by the day, week, month, or year
- Displays volts, amps, and wattage within 0.2 - 2.0percent accuracy
- Compatible with inverters; designed for use with AC 115-volt appliances

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | P3 |
| Part Number | P4400 |
| Item Weight | 5.6 ounces |
| Product Dimensions | 8.4 x 2.1 x 6.1 inches |
| Item model number | LGP4400 |
| Batteries | 1 CR123A batteries required. |
| Is Discontinued By Manufacturer | No |
| Size | Original version |
| Color | No Color |
| Style | 1 Pack - Model P4400 |
| Material | Other |
| Pattern | Monitor |
| Power Source | air-powered |
| Voltage | 115 Volts |
| Amperage Capacity | 15 Amps |
| Item Package Quantity | 1 |
| Number Of Pieces | 1 |
| Display Style | LCD |
| Certification | No |
| Special Features | Portable |
| Usage | personal |
| Included Components | usage monitor |
| Batteries Included? | No |
| Batteries Required? | No |
| Warranty Description | 1 Year Limited |

## Images

![P3 P4400 Kill A Watt Electricity Usage Monitor - Image 1](https://m.media-amazon.com/images/I/61FOAk4UA5L.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: what is the difference between the p4400 and the p4460?**
A: This device, the P4400, will reset all of its timed measurement values to zero if power is lost or the device is unplugged. The P4460 has "non volatile" memory, using a battery to provide the necessary voltage to power the (S)RAM memory, which means that it will not lose the data if power to the 4460 is lost. The P4460 also will let you input the cost per KWH from your provider to calculate the cost to operate the appliance over a week, month and year (assuming that your use is the same during the extrapolated period as it was during the measurement period). For me the data retention feature is well worth the extra $4 since I want to keep track of the energy used by a window air conditioner which will vary by the outdoor temperature, the sun hitting the building, the humidity, etc.

**Q: .most of my outlets are 20 amps or more, the killawatt is only 15 amps does that make a difference in calculations, the garage is 40 amp.**
A: This will only plug into a 120 VAC outlet. The standard 120 VAC outlet in almost all homes is only rated 15A continuous duty, but can take more for a second like when a room air conditioner compressor starts up. This is probably following those same rules. If the wiring is 12 gauge or thicker, it can be hooked to a 20 amp breaker even though all of the outlets in the average house are rated 15A, at least in most states. The reality of the matter is that wiring and outlets can always take somewhat more than the ratings and everything is oversized for safety. But is is always considered unsafe to plug in any device that uses more than 15 amps into a typical house outlet. An exception is commercial outlets that fit both home devices and heavier duty commercial device plugs and those outlets are usually rated at 20 amp. Those outlets are more common in businesses and uncommon in homes. An air conditioner or commercial refrigerator that uses more than about 10 continuous amps will normally be a 240 volt appliance and require different type of outlet designed for 240 volts, same is true of typical electric clothes dryer and this device would not adapt to those.

**Q: Will this work with two prong (non-grounded) outlets?**
A: Be Careful- defeating a polarized plug can be dangerous.  The wide prong is neutral and connected to ground. The narrow prong is "hot" (energized) compared to ground. Some devices such as tools, chargers, and others use polarization to reduce the chance of electrical shock. If the device, such as most lamps, doesn't have a polarized plug then there is no concern, an adapter or extension cord is fine. If a device has a polarized 2 prong plug and you decide to use an adapter anyway, make sure the KillaWatt's plug's small slot on front is aligned with the wall plugs small slot and the larger slot on front aligns with the larger slot on the wall plug to maintain polarity.   It is impossible to reliably maintain polarity using an extension cord so I would never attempt it. I would never cut off the ground prong, the blade prongs on the KillaWatt are the same size because the ground prong aligns the correct prongs with the wall plug so they do not need to be different sizes. Once you cut off the ground prong the odds are 50/50 of dangerously reversing the polarity of the plug on the front of the KillaWatt since it may, or may not, be plugged in correctly. Similarly if the wall plug slots are both the same size you are once again at 50/50 odds of plugging the KillaWatt in incorrectly with an adapter making the KillaWatt itself an "adapter" permitting you to plug polarized plugs into unpolarized wall plugs. Once again if the lamp etc doesn't have a polarized plug this is not an issue. (If you want to know more about why polarization makes things safer just ask)

**Q: Hi, is this unit able to capture peak current draw? I want to see if my audio amplifier ever gets close to tripping my breaker.**
A: I don't have it but from what I know about it is that you can measure watts for long period of time, So - reset meter, set it to continuously measure watt*hour (WH, watt for 1 hour=60 minutes*60=for 3600 seconds), connect your turned off amp, turn it on and immediately turn it off exactly after 1/2 second. Meter SHOULD show wattage consumed for 1/2 second because they say it measures power FEW TIMES PER Second (though still will be measuring after amp will be turned off, but it is ALMOST not consuming power) - that will be your surge power - multiply it by 3600 and by 2 (because 3600 for hour and for whole 1 sec it would be twice higher) and divide it on 115, or whatever voltage will be during measurements (put voltmeter to measure voltage, or just measure voltage before starting test, though voltage can can change fast). And you will get average current for first 1/2 sec. If you manage to turn it off exactly after 1/4 sec (but don't forget to multiply measured WattHour by 3600 and by 4, because 3600 higher for 1 hour and for whole 1 sec it would be 4 times higher) then measuring current surge will be more accurate. This calculation imitates WattHours consumed by amp as if it worked with average current equal to surge current for 1 hour, and that is why you divide those WattHours on voltage to get average current equal to surge current (which actually happened only during part of first second). So, if meter accurate enough to measure small power consumption then all this will work.But remember: amp MAY not like it, though SHOULD Tolerate such thing - anyway, don't blame me if something happens to it. I would do that myself, i believe this is not unusual for amp.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Accurate, Simple, and Addictively Useful
*by E***S on October 20, 2025*

Accurate, Simple, and Addictively Useful The P3 Kill A Watt Electricity Usage Monitor is one of those inexpensive gadgets that quietly changes how you think about energy use. I first bought it to see how much power my old refrigerator was pulling—and ended up testing every appliance in the house. Setup is instant: plug it into the wall, connect any device, and the bright LCD display immediately shows volts, amps, and watts in real time. Leave it running for hours or days, and it totals up the kilowatt-hours (kWh), letting you see exactly what that appliance costs you per day or month. What makes it so helpful is how accurate and intuitive it is. You don’t need to be an engineer—just read the wattage and multiply by your utility rate. I found a few “phantom” power hogs drawing 10–20 watts even when off (like a cable box and an older UPS). It’s also great for testing PC builds, aquarium setups, or any electronics to ensure your power supply is sufficient. The build quality is solid, and the display remains easy to read even after years of use. The only caution: it’s designed for 115V North American outlets only—not for international use. Bottom line: A must-have tool for anyone curious about energy use or looking to cut electric bills. Simple, accurate, and surprisingly enlightening—it pays for itself quickly.

### ⭐⭐⭐⭐⭐ Works as intended.
*by D***E on December 3, 2025*

Works great helped estimate electrical usage on a few big appliances.

### ⭐⭐⭐⭐⭐ Extremely Useful
*by N***T on September 20, 2012*

Don't bother buying the more expensive models of the Kill-A-Watt. The P3 model is more than enough. It will give you how many watts your device is drawing, as well as the number of amps, number of volts (at the outlet), and frequency (60 hertz). It also keeps track of the total number of kilowatts hours your device has used during the length of time you have been monitoring the device. To calculate how many kilowatt hours your device will use in a month, you just need a bit of simple math: (Watts/1000) x (number of hours device is turned on per day) x (31 days) = Kilowatt hours per month Example for a 100 watt light bulb that is left on continuously for a month: (100/1000) x 24 x 31 = 74.4 kwh per month Note that a kilowatt is 1000 watts and 1 kilowatt hour is the equivalent of ten 100 watt light bulbs burning for 1 hour. Electricity is billed in kilowatt hours so you can find out how much each kilowatt hour costs by contacting your electric company or looking on their website. Your electric bill should tell you how many kilowatt hours you used in a given month. It is easy to calculate how many tons of CO2 your electricity use produces. The EPA website estimates 6.8956 x 10-4 metric tons of CO2 per Kilowatt hour. I pay for 100% wind power through my utility, which only adds about $1.80 per month to my electric bill and we use a lot of electricity (about 1200 kwh per month). Part of this large number is the fact the landlord installed an electric water heater (a gas water heater would be much more efficient). I finally ordered a P3 Kill-A-Watt and wish I had ordered one 10 years ago because it would have paid for itself many times over. If you check various items in your home, you will be surprised at how much electricity things use. Many electrical devices draw 2 to 5 watts or more when they are turned off but left plugged in! When you count how many things you have plugged in in you home, this adds up. I now unplug things I am not using. One of the biggest energy wasters is the common light bulb, which wastes 98% of its energy as unwanted heat. For comparison, I have an old style Sony 32 inch TV (picture tube, not flat panel) that draws 150 watts. A single reading lamp with a common 150 watt bulb uses the same amount of electricity as this large TV. You are much better off using compact fluorescent bulbs which use FAR LESS electricity. Amazon sells GE compact florescent 100 watt (equivalent) bulbs that actually use only 26 watts. (Type "compact fluorescent 100 watt" into Amazon search). The compact florescent GE 60 watt (equivalent) bulbs actually use only 13 watts. These bulbs screw right into your existing lamps and light fixtures and will pay for themselves many times over. The downside of compact florescent bulbs is that they contain a significant amount of mercury (about 5 grams). There are special cleanup procedures you should follow if you accidentally break one inside--open a window, do NOT vacuum--see the EPA's "Cleaning Up a Broken CFL" article for the full procedure [...] Because compact florescent bulbs contain mercury, they must not be disposed of in regular trash. Call your local municipality to learn how to dispose of items that contain mercury--many municipalities have recycling programs for mercury containing items. A much better alternative to compact florescent bulbs are LED bulbs (do not contain mercury) which are a new technology and consequently expensive at the moment but prices will come down with time. A final note on the Kill-A-Watt regarding computer power supplies. I build computers and, prior to owning a Kill-A-Watt, ended up buying much larger (and more expensive) power supplies than I really needed because of some misleading information on the web. For example, the computer I am typing this on with a good Intel CPU and an expensive video card draws 130 watts at idle and 270 watts with both CPU and video card fully loaded (running Prime95 and 3DMark simultaneously). Unfortunately, I put a 750 watt power supply in this computer, which was totally unnecessary. It is important to purchase a high quality power supply, but you definitely don't need a 750 watt power supply for a computer that draws 270 watts at full load.

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*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-03-12*