Improvements in rechargeable battery tech and intelligent software have dramatically changed the way we live. Smart televisions and lighting systems improve our sensory environment, while other automated home devices like vacuum cleaners, thermostats, and refrigerators eliminate many more mundane tasks. Similarly, robotic lawn mowers can now keep the grass at just the right height, eliminating a time-consuming weekend chore. These devices may be cheaper to own and operate than gasoline-powered mowers while making very little noise and producing no exhaust emissions. They can easily maintain up to an acre or more on most types of terrain, and they work automatically so those with lawns have more time to relax.
All of which no doubt sounds great—but how well do these robots actually perform? To find out, we put some popular models through their paces on real-life lawns. Read on to learn about the criteria we used to select these mowers, then check out the product reviews to find out how each one did on our test turf. Anyone in the market for a new mower may discover that a robot model might be a smart, time-saving investment. R2-D2 would surely approve!
- BEST OVERALL: Worx Landroid M Robotic Lawn Mower
- BEST BANG FOR THE BUCK: Robomow RX20 Robotic Lawn Mower
- UPGRADE PICK: Husqvarna Automower 415X
- BEST FOR STEEP HILLS: MowRo RM24 Robotic Lawn Mower
- BEST FOR LARGE LAWNS: Husqvarna Automower 115H
What to Consider When Choosing the Best Robot Lawn Mower
Shopping for new technology can present a bit of confusion. It’s important to take some time to sort through the various functions and features, as well as your unique needs, to identify the best product. Consider the following factors when shopping for a robotic lawn mower.
To begin the search for a new robot mower, get an accurate measurement of the area it will mow. Measure the lawn’s square footage, not the size of the lot, and exclude square footage taken up by the house, driveway, landscape beds, and any other feature that is not grass. Often only half of the square footage of a residential lot is lawn space, and sometimes even less.
Light-duty or small robot lawn mowers are best for areas up to a quarter of an acre, or about 11,000 square feet. Midsize robot lawn mowers cut up to half an acre, or about 22,000 square feet. Large robot lawn mowers can cut up to 1 acre, or 43,560 square feet, or more.
Factors that affect how much space a robot lawn mower can cut include battery runtime per charge, the mower size, and the speed it travels. The “up to ‘X’ square feet” amount that manufacturers claim is calculated with ideal mowing conditions in mind. Mowing conditions including slopes; obstacles; irregular lawn shapes; and grass type, thickness, and growth rate may all inhibit a mower’s efficiency and capability.
Look for a mower that can cut the entire yard on a single battery charge if possible. For larger yards, it may be necessary to divide the lawn space into two or three smaller mowing zones that the mower can cut on different cycles. Not all robotic mowers have the ability to create and schedule multiple zones within a single boundary wire, so be sure to buy a mower with that capability if necessary to suit the property size.
Basic robot mowers work on flat yards and slopes of up to 15 percent (1.5 feet of rise per 10 feet of linear distance). Yards with garden beds, boulders, pathways, and/or steeper slopes require a more capable model. Look for one with onboard collision detection systems, GPS, all-wheel drive, and/or multi-zone programming capability to navigate complex yards.
Grass type, weather conditions, and terrain influence a lawn’s optimal mowing height. Warm-season grasses like Bermuda, zoysia, and centipede should be mowed to from 1 to 3 inches high, while cool-season grasses such as fescue, bluegrass, and perennial ryegrass should be mowed to between 2.5 and 4 inches.
That said, allowing grass to grow taller than normal in extreme heat and drought helps protect the roots from dieback. Smooth, flat ground makes it easier to mow lower, while rough terrain requires additional clearance. We recommend buying a robotic mower that allows as much mowing height flexibility as possible within the range for the particular lawn type.
Robot mowers are kept in the yard by a low-voltage electric perimeter boundary wire installed at the edges of the lawn and around permanent obstacles like trees, paved areas, and buildings. An onboard computer tells the mower when to mow and when to recharge. Just program the mowing schedule and set the blade height, and the lawn mower does the rest. Many robotic lawn mowers are Bluetooth capable or Wi-Fi connected, so you can program them with an app on your smartphone.
Power Source and Battery Life
Robot mowers charge automatically at a home-base station. The base station serves as the charging port and the boundary wire hub. The same power source that charges the mower’s battery also sends a low-voltage current through the boundary wire to keep the mower in bounds. A single power cord plugged into a nearby GFCI household outlet provides the needed electricity.
These mowers typically use rechargeable lithium-ion batteries, though some use lead acid batteries or other types. Depending on the model and mowing conditions, a robot lawn mower can operate between 1 and 2.5 hours per battery charge. Batteries typically need 30 minutes to an hour to recharge. Robot lawn mower batteries tend to last approximately 3 years on average.
Onboard sensors, Bluetooth connectivity, mobile apps, and compatibility with personal digital assistants may all let users program a robotic mower. On its programmed mowing schedule, the mower starts and recharges itself, returning to its docking station when it has finished the job. Collision sensors and boundary wire sensors keep the mower on the lawn and protect non-grass areas.
Some robotic mowers have a manual mode used to trim enclosed spaces. In manual mode, the robot mower can be moved to a secondary location—inside a fenced area of the yard, for example—and it will mow without further programming. In this setting, the robot mower uses either extra perimeter wire or an onboard collision sensor to stay inbounds.
Many robot mowers will alert the user’s smartphone when there is a problem, if its blades need to be changed, or if the machine is moved off the premises. Mobile apps can also allow the robot mower to be monitored and controlled remotely via a smartphone or digital assistant.
Robotic mowers are quiet but not silent. They produce an average of 50 to 70 decibels, which is similar to the sound levels of a quiet refrigerator, a calm conversation, or the noise inside a car traveling at 60 miles per hour. A gasoline-powered push mower produces 95 decibels, or about 50 percent more noise than a robot lawn mower.
Robot lawn mowers are small enough that a thief could carry one away. For that reason, many models require a personal identification number (PIN) for operation. Others feature alarms, security alerts, and GPS tracking that kicks in if the unit is removed from the owner’s property. Since robot lawn mowers are fairly quiet, people often program them to run at night as a theft deterrent.
Robot lawn mowers have safety features to protect the user and others in its cutting area. The machine moves slowly so pets, children, and others can see it coming and get out of the way. Collision sensors slow or redirect the mower as it nears an obstacle. An automatic shutoff kicks in if the machine is lifted, stopping the blades from moving. And the mower has recessed blades mounted away from the edges of the machine to reduce the chance of cutting hands and feet that come too close.
Most robot lawn mowers are built to withstand outdoor conditions during the mowing season. Some robotic mowers can run in the rain, but it is not recommended since wet grass doesn’t cut as smoothly and wet conditions can spread fungal diseases to the lawn. Some robot lawn mowers have rain sensors that stop, skip, or delay a scheduled mowing in rainy conditions. Other robot mowers can have their cutting schedule manually overridden so users can turn it off if rain is in the forecast. Still others link to a weather app that will turn the mower off if rain is predicted.
Docking stations are weatherproof during the mowing season. Still, in stormy weather where lightning is predicted, unplugging the system provides the best protection. Extended periods of damp, subfreezing weather shorten the mower’s life span, so the mower and its docking station should both be stored indoors in the winter.
Our Top Picks
We measured the following robotic lawn mowers against our shopping considerations and put them to work during a monthlong home trial. Find out why we recommend them among the best robot lawn mowers available.
The popular Worx Landroid robotic mower lineup includes models S, M, and L for yards up to ⅛ acre, ¼ acre, and ½ acre, respectively. While they offer many similarities, we found that the WR147 Landroid M offers the best combination of capability and affordability. It is powered by a 20V 4Ah lithium-ion battery for 2 hours of runtime per 90-minute charge. It can mow on a 20-degree slope, thanks to a pair of high-efficiency brushless wheel motors that provide extra traction. The Landroid’s 8-inch self-leveling mowing disc cuts closer to the edges of the yard than many competitors. The blade height manually adjusts from 1.5 to 3.5 inches.
Landroid connects to a home Wi-Fi network via Bluetooth and automatically keeps its own software up to date. Users can easily set or adjust the custom mowing schedule or monitor the mower on the go via the Landroid mobile app. An integrated rain sensor stops the mower from cutting if rain starts and sends it back to its charging station.
The Landroid M performed at or near the top in most of our testing rubric categories. Assembly and programming were easy, mowing was reliable with excellent coverage, communication through the mobile app was intuitive, and runtime was superior—all for a very competitive price. Runtime was especially impressive: We clocked it at 2 hours 35 minutes, the longest of all the mowers we tested.
Unfortunately we subtracted points for poor docking ability. Landroid was the only mower we tested with recharging contacts located on the side of the machine rather than the front or back. To recharge, it must be perfectly positioned in relation to two flexible contact points as it passes over the base station; otherwise, it continues tracking along the perimeter wire without stopping. After resetting the base station three times and ensuring it was absolutely level in all directions with a long, straight approach, we finally achieved satisfactory results.
Aside from that issue, Landroid provides outstanding overall functionality for the price. Available upgrades include the ACS module that prevents collisions, Find My Landroid GPS cellular module, Radio Link module to extend Wi-Fi connectivity for improved artificial intelligence, an Off Limits module for wire-free no-mow zones within the main mowing area, and the Landroid Garage.
- Coverage area: 0.25 acre (10,890 square feet)
- Mowing height range: 1.5 to 3.5 inches
- Slope rating: 20 degrees
- Easy installation
- Numerous upgrades available
- User-friendly mobile app
- Excellent runtime per charge
- Value price point
- Base station must be installed perfectly
- Some desirable features are not included
Get the Worx robot lawn mower on Amazon or at The Home Depot.
Those seeking a little mowing help without navigating extensive setup menus may find the Robomow RX20 to be just the ticket. It easily mows a small yard at the push of a button, or it can be controlled remotely via mobile app and Bluetooth connection. The app lets you set a weekly mowing schedule and program different starting points. Powered by a 12V 4.3Ah lithium-ion battery, it provides up to 2 hours of runtime per charge—but recharges in a lengthy 8 hours. It is rated for flat or gently rolling smaller yards up to 2,178 square feet. Unlike the other mowers we tested, the RX20 uses a single blade that only needs to be replaced once per mowing season.
Setup and basic programming were similar to all the other models we tested. Unlike the others, though, the battery arrived totally depleted and had to charge for 48 hours prior to the first mowing. Then we were able to manually initiate the first mowing, download the Robomow app, and program a weekly mowing schedule. Scheduling only allowed a single daily mowing time rather than multiple mowings with recharging times in between. The controls only allow for manual operation. To program a weekly schedule, we had to use the app while within Bluetooth range of the mower.
The RX20’s limited terrain capability necessitated assembling an entirely different 1,200-square-foot testing area on mostly flat ground with centipede grass; this space included a narrow passage connecting two broader areas. Mowing went well on the flat ground, and the robot had no trouble navigating the narrow passage. Docking worked smoothly when mowing was done. While this is not the robot for complicated spaces, those with a relatively flat, unobstructed yard may find this affordable no-frills robot mower ideal for keeping the grass looking great.
- Coverage area: 0.05 acre (2,178 square feet)
- Mowing height range: 0.5 to 1.75 inches
- Slope rating: 8.5 degrees
- Easy setup and operation
- Intuitive app controls
- Budget-friendly price point
- Great for flat, clear ground
- Limited terrain capabilities
- Only one scheduled automatic mowing per day
- Must be within Bluetooth range to control via the app
Get the Robomow robot lawn mower at Amazon, The Home Depot, or Best Buy.
Here is a well-equipped mower for warm-season grasses up to ⅓ of an acre, especially lawns with challenging obstacles, narrow passages, and sloped terrain. With a mowing height range of 0.8 to 2 inches, the Husqvarna Automower 415X is designed for maintaining low-mow grasses like zoysia, Bermuda, and centipede. It is powered by an 18V 2Ah lithium-ion battery that delivers a runtime of 50 minutes per charge and recharges in 60 minutes. This mower features a high-resolution onboard display, rugged poly front bumper, LED headlights, and coarse-tread wheels that easily handle slopes up to 40 percent.
The Automower 415X is loaded with communication and control features, beginning with cellular and Bluetooth connectivity. It is easily controlled via the Automower Connect mobile app and is compatible with Amazon Alexa and Google Home smart devices. Husqvarna’s intelligent mapping technology uses GPS sensors to virtually map the lawn, enabling zone control with customized settings, and real-time tracking through the app. This high level of communication pairs nicely with precision control and automated features like electric height adjustment, automatic passage handling, remote location starting, spiral- and spot-cutting capabilities, wireless firmware updates, theft protection system with GPS tracking, and more.
The Automower 415X arrived for testing with everything we needed for a quick and easy DIY installation. The layout and setup were similar to the other models we tested but with the unique addition of a central guide wire running through the middle of the mowing area to assist with navigation back to the home base. Initial programming was fast and intuitive with the mower’s onboard controls. After downloading the app, we spent some time customizing mowing options, adding the targeted mowing height and spiral mowing options. Targeted mowing automatically lowered the cutting height each day until our preselected height was achieved. With spiral mowing engaged, the mower automatically detects extra-tall or dense growth and mows that isolated area in a spiral pattern. These two options were especially helpful in combination, as we needed to get our overgrown Bermuda grass under control.
Our testing lawn was an irregularly shaped area encompassing 1,200 square feet, with a tree isolated by the boundary wire near the middle and two larger lawn areas on either side. Part of the test area included a steep slope, close to 50 percent in one small area, and the 415X had no trouble. We noticed after the third or fourth mowing that the robot was making more efficient linear cuts and less frequently getting caught up in multipoint turns.
During the target-height adjustment period, the mower seemed to focus more time on a section after it had been sufficiently cut, then running out of battery before fully cutting the other section. Once the target was achieved, however, daily mowing at 1.25 inches kept the grass looking great. Docking at the base station went perfectly every time. Easy setup, reliable operation, smart tech, and a lower mowing height range make this a good choice for most small to midsize yards with warm-season lawn grass.
- Coverage area: 0.37 acre (16,117 square feet)
- Mowing height range: 0.8 to 2 inches
- Slope rating: 22 degrees
- Precision control features
- GPS-assisted navigation
- Easily navigates obstructions and difficult terrain
- Cellular and Bluetooth connectivity
- Premium price point
- Limited runtime per charge
Get the Husqvarna Automower 415X robot lawn mower at Amazon, Lowe’s, or Tractor Supply Co.
The MowRo RM24 Robotic Lawn Mower is a simple choice for small to midsize yards and budget-conscious consumers. Its efficient brushless motor is powered by a 28V 4Ah lithium-ion battery that produces 2 hours of runtime per charge; recharging takes about an hour. The RM24 mows up to a quarter acre, including steep slopes up to 30 degrees, on schedule every 48 hours or on demand. Rain, tilt, and impact sensors allow it to operate safely, automatically avoiding bad weather, excessive slopes, and obstacles. The mowing height manually adjusts from 1 to 2.5 inches. All scheduling and other operations are performed via the onboard control panel.
In our tests, the simple onboard controls and reliable operation of the MowRo RM24 made it one of the easiest robot mowers to set up and operate. It used the same boundary wire and base station setup as the rest of our testing group. However, it lacks the precision control features and connectivity found in the other models tested. We didn’t miss the zone mowing capability and Bluetooth connectivity so much but wished for more frequent scheduling options. With its larger than average cutting head and slope-conquering wheel motors, it seems that this mower could handle a much larger yard if scheduling ability was more robust. Still, this unit offers a good price-to-value ratio for those with steep terrain.
- Coverage area: 0.25 acre (10,890 square feet)
- Mowing height range: 1 to 2.5 inches
- Slope rating: 30 degrees
- Easily navigates steep slopes
- Simple controls
- 2-hour runtime per charge
- Mows on schedule every 48 hours, or on demand
- Onboard controls are the only interface; no mobile app
- Lacks precision control features
- Only capable of one scheduled mowing every 48 hours
Get the MowRo robot lawn mower on Amazon or at The Home Depot.
The Husqvarna Automower 115H mows all kinds of grass up to 0.4 acre. Its durable 18V 2Ah lithium-ion battery delivers 60 minutes of runtime per charge and recharges in just an hour. The cutting head manually adjusts from 2 inches to 3.6 inches, for either warm-season or cool-season grasses, and it’s rated for slopes up to 17 degrees. Bluetooth connectivity lets users control the 115H via the Automower Connect mobile app. Adjust the schedule, start or stop mowing on demand, monitor status, and order replacement blades all in one convenient location. The unit has theft protection with a PIN code and alarm system.
The Automower 115H impressed us as a great choice for most suburban lawns. It easily navigated our test lawn’s slope and obstacles, reliably mowing on schedule, and docking securely. The lawn’s appearance was consistent throughout testing, without any obviously missed spots. Working with the Automower Connect app, it was easy to program the schedule, set up different starting points, and pause and restart a mowing program during an active cycle. The guide wire helped the Automower navigate efficiently through a narrow corridor from one broad space to another. It’s worth noting that the lack of GPS technology makes this a “less smart” mower than the model 415X reviewed here. For instance, the 115H did not seem to adjust its mowing patterns and obstacle avoidance as quickly as its more intelligent colleagues did. But this model makes a great choice for larger yards and maintaining taller grass.
- Coverage area: 0.4 acre (17,424 square feet)
- Mowing height range: 2 to 3.6 inches
- Slope rating: 17 degrees
- Mowing height range suits most types of grass
- Works on slopes up to 30 percent (17 degrees)
- Intuitive programming via mobile app
- Program up to 3 different starting points for efficient coverage
- Premium price
- Only 60 minutes of runtime per charge
Get the Husqvarna Automower 115H robot lawn mower at Amazon, Lowe’s, or Tractor Supply Co.
For a robotic lawn mower to be considered the best, it should offer a wide range of built-in functionality along with readily available upgrade options and come in at a competitive price. That’s why we chose the Worx Landroid as our top pick. Setup and operation are straightforward and reliable, a variety of accessory options are available to boost functionality, and the price is significantly lower than the more technologically advanced Automower series. Shoppers not all that interested in top-of-the-line tech, who simply want a capable, reliable mower to help out with a little patch of grass, may find that the Robomow RX20 can provide satisfactory results while saving a few hundred dollars.
How We Tested the Best Robotic Lawn Mowers
All of the robotic mowers we tested use 14-gauge low-voltage wire to establish the barrier. So, we assembled two barriers around two 1,200-square-foot patches of lawn, one with Bermuda grass and a steep slope and one mostly flat with centipede grass. Each test area included two large open spaces connected by a narrow bottleneck corridor. Most of the mowers were tested on both test areas, with the exception of the Robomow.
To test the mowers, we scheduled daily mowing for 7 days in each location. We observed the ease of programming and communication with the mower as well as its actual performance. Criteria to be included in this guide were as follows:
Consistently reliable mowing on schedule and returning to the base station after initial setup and first-day adjustments
- Consistently navigating the narrow corridor to mow both large areas
- Avoiding random obstacles intentionally left within the boundaries
- Returning to the base station in the event of rain or sprinklers
- Avoiding excessively steep slopes without becoming stuck
- Complete coverage of the test area—no noticeable missed spots for the week
Still not sure how to choose the best robot lawn mower for you? Read on for info and tips to facilitate your decision.
Q. How does perimeter wire work?
Perimeter wire runs from the charging station, around the edge of the yard, and back to the charging station. It carries a low-voltage electrical signal that keeps the mower inbounds. The wire should be installed at the beginning of each mowing season and taken down for storage in winter. Installation is typically a DIY project, but some sellers offer professional installation.
Q. How often should I use a robotic lawn mower?
Robotic mowers are designed to cut several times per week. When grass is growing really fast, the robot mower should run every day or every other day. When grass grows more slowly, mowing 2 or 3 times per week is sufficient.
Q. Can I use a robot lawn mower while it rains?
Some robotic mowers can operate in the rain; others cannot. However, you’ll get a cleaner cut and reduce the spread of disease in your lawn by mowing only while the grass is dry.
Q. How long do robot mowers last?
The mower itself should last 10 years or more. Mower blades last about 2 months. They cannot be sharpened; they must be replaced—think of them as you would a disposable razor blade. Rechargeable batteries for robot mowers last about 3 years on average.