Navimow X420
3 independent reviewsRead the findings →The entry to Segway's heavy-duty, four-wheel-drive Navimow range, built for large, hilly lawns. It's one of the quickest mowers around, with gentle turns on the grass. It's heavy, too wide for narrow gaps and weak at the edges.
See the alternatives below, or switch market.
Where it sits in Segway Navimow’s range
- i2 AWDCompact all-wheel-drive model for lawns up to 800m²
- i220 LiDAR ProLaser, satellite and camera guidance for 2,000m² · £1,954
- Navimow X420This model
- Navimow X430Same X4 mower rated for 3,000m²
- Navimow X450Largest X4 version, rated for 5,000m²
Feedback
What reviewers found
Three home tests of the X420, all in Germany: heise bestenlisten over several weeks in a twisty garden with several zones, inside digital in a garden with slopes and narrow passages, and Basic Tutorials on a lawn with straight edges. They praise obstacle spotting, the fast cut and gentle turns. Navigation had its slips, though: failed passages, boundary overruns and a wedge while mapping. They disagree on edges: inside digital measured a 3cm gap, while heise bestenlisten and Basic Tutorials were left with noticeably more. An owner on Reddit owner who switched from a LUBA 2 found setup easy.
heise bestenlisten, hands-on, Several weeks at home, Aug 2026 · inside digital, hands-on, May 2026 · Basic Tutorials, hands-on, Jul 2026
Cut quality and edges
Mixed resultsThe finish is excellent: heise bestenlisten got near-perfect parallel stripes fast. Edges split the testers, with inside digital measuring just 3cm left while heise bestenlisten found more left at hard edges than rivals with side trimmers.
Setup and boundaries
Reviewers rate it highlyNo wire, and the aerial is optional. heise bestenlisten liked editing boundaries later in the app, though automatic mapping failed in its awkward garden, and inside digital and Basic Tutorials both recommend driving the boundary by hand.
Navigation
Mixed resultsMostly reliable, but it's a wide machine. A 70cm link between lawns defeated it for heise bestenlisten, which also saw it cross mapped borders and stick at drops. inside digital got it through 90cm, and Basic Tutorials saw it briefly wedge itself while mapping.
Slopes and rough ground
Not enough evidenceOnly inside digital tested slopes, finding it handled them and uneven ground without effort and never lost grip. heise bestenlisten found it gentle on turf but saw it get stuck where the ground dropped away.
Obstacles and safety
Reviewers rate it highlyAll three were impressed. heise bestenlisten found dogs, small balls and a hose recognised every time, and inside digital saw it pick out a small ball and a hose and stop for a person walking too close.
Weather
Not enough evidenceNo review we use tested it in rain. Basic Tutorials saw it cut dense, damp grass without clogging.
App and software
Reviewers rate it highlyinside digital praised the app as easy to use with features rivals lack, such as per-weather settings, and heise bestenlisten found it clear and well laid out, though there's no live camera view.
Upkeep
Not enough evidenceNo review we use has reported on cleaning or blade changes yet.
Reliability and support
Not enough evidenceNo review we use has run it long-term or judged Segway's support.
Value
Not enough evidenceOnly inside digital weighed the cost, noting the yearly 4G fee after the first year but otherwise rating it highly. No other review we use judged value.
Verdicts come from independent, hands-on, finished reviews. An area needs at least two of them before we say more than “Not enough evidence”. We don't score robots ourselves. How this works
Fast, and kind to the lawn
heise bestenlisten timed it mowing a flat 240m² patch in 66 minutes, the fastest of any mower it has tested, with near-perfect parallel stripes and a flawless finish. Its steerable front wheels left the turf unmarked in turns, which heise bestenlisten found much gentler than the LUBA 3 or Dreame A3. inside digital says it never lost grip and didn't churn up even soft ground, and Basic Tutorials saw it handle dense, damp grass without clogging. On a big lawn, that speed is the main reason to buy it.
Edges: 3cm or 10cm?
The testers don't agree here. inside digital measured just 3cm left at the edge, better than it expected without a trimmer. Basic Tutorials saw anything from a few centimetres to about 10cm where the edge sat higher than the lawn, improved by switching on the edge setting. heise bestenlisten found more grass left at hard edges than rivals with side trimmers, and by default it kept well clear of bushes and overhanging branches until those areas were marked as camera-off zones. Flush edges suit it; raised ones will need a strimmer.
Too wide for tight gaps
At 61cm wide, gaps are the limit. heise bestenlisten's 70cm link between two lawns defeated it, and it sometimes crossed the mapped boundary and got stuck where the ground dropped more than 7cm. Stepping stones set into the lawn confused it until they were marked as a camera-off zone. inside digital got it through a 90cm passage on a slope, and Basic Tutorials managed passages under a metre, though it briefly wedged itself between a bucket and an umbrella stand while mapping. Measure your narrowest gap first.
Obstacle spotting is a strength
All three testers were impressed. heise bestenlisten found dogs, small balls and a garden hose recognised every time. inside digital saw it pick out bushes, a small ball and a hose, and it stopped and spoke a warning when the tester walked too close. Basic Tutorials found tennis balls and pets spotted and avoided, with a brief pause whenever a person came near. That's a good record, but it doesn't mean it'll spot every object or animal. Clear the lawn before mowing, and note the app has no live camera view.
Setup is easy; auto-mapping less so
There's no wire, and the aerial in the box is optional. Only the dock needs Wi-Fi, Basic Tutorials notes. Automatic mapping failed in heise bestenlisten's awkward garden, and both inside digital and Basic Tutorials recommend driving the boundary by hand. heise bestenlisten liked that you can edit boundaries later in the app without re-driving them. An owner on Reddit owner found positioning the dock and mapping easier than on a LUBA 2 and missed only the old mower's camera view. Cutting height adjusts in 5mm steps, per zone.
Long runs, slow charging
heise bestenlisten got about two and a half hours of mowing on flat ground, well beyond Navimow's figure of one and a half. Charging went the other way: about three hours on a 35°C day and just under two the next, against a claimed 75 minutes. It still gets through a lot of lawn per charge. Plan the schedule around longer pauses than the spec sheet suggests, especially in hot weather.
All three tests and the owner report cover the 2,000m² X420. The X430 and X450 are rated for bigger lawns and aren't covered here.
Our take
Should you buy the Navimow X420?
Best for: Large lawns with slopes or rough ground. Skip it if: Your lawn has narrow passages or edges you want cut closely.
The X420 is worth considering for a large lawn with generous passages if mowing speed and gentle turns matter. Only one review specifically assessed slopes, and none verified the full 84% claim. Expect edge trimming, possible trouble at drops and charging pauses longer than the specification suggests. The LUBA 3 is smaller but can scuff soft ground; the GOAT A3000 LiDAR Pro adds edge trimming but also struggled with holes and long tufts.
The X420 is the entry point to Navimow's X4 series, the heavy-duty range that sits above the smaller i2 mowers. It's the 2,000m² version; the X430 and X450 are rated for 3,000 and 5,000m². Four driven wheels with steering at the front, two cutting discs and a 43cm cut make it one of the quickest robot mowers around, and Navimow rates it for 84% slopes. It navigates with satellite positioning corrected over the mobile network plus cameras that see all round, so there's no wire and usually no aerial.
The catch is size. It weighs nearly 29kg and is 61cm wide, so gaps narrower than about 70 to 90cm can defeat it, and it's overkill for a small, flat lawn. There's no side trimmer, and testers disagree on how much grass it leaves at the edges. 4G is free for the first year and paid after that, while the positioning corrections stay free.
Before you buy
The questions people ask about this one
Does it need a boundary wire or an aerial?
No wire. It uses satellite positioning corrected over the mobile network plus cameras, per the specifications. An aerial comes in the box, but Basic Tutorials and heise bestenlisten both describe it as optional. The dock needs Wi-Fi and a clear area in front.
Will it cope with my slope?
It's rated for 84% (40°), per the specifications. inside digital found it handled slopes and uneven ground without effort and got through a 90cm gap on a slope. None of the testers reports measuring the full rating, and heise bestenlisten notes it can get stuck on drops of more than 7cm.
Can it handle two lawns or a narrow passage?
Two lawns, yes; narrow passages, not always. heise bestenlisten's 70cm link between zones was too tight for its 61cm body. inside digital got through 90cm, and Basic Tutorials managed passages just under a metre. Allow at least that much.
How close does it cut to the edge?
It depends on the edge. inside digital measured 3cm, Basic Tutorials saw up to about 10cm by raised edges, and heise bestenlisten found more left at hard edges than rivals with side trimmers. Flush edging suits it best.
Is there a subscription for 4G?
After the first year, yes. One year of 4G data is included and then renewable yearly, per the specifications. heise bestenlisten says the network positioning service itself stays free. 4G covers remote control, alerts and GPS tracking.
Alternatives
Other robot lawn mowers to compare.
LUBA 3 AWD
Why consider it: Three home tests rate its wide cut and its climbing highly, in a smaller, lighter body.
The compromise: It can scuff soft ground when it turns on the spot, and it's still heavy at about 19kg.
GOAT A3000 LiDAR PRO
Why consider it: A side string trimmer and a 33cm cut make it one of the better options for tidy edges.
The compromise: Testers with bumpy ground or long tufts found it stuck in holes or steering round grass.
Automower 435X AWD NERA
Why consider it: All-wheel drive for big, steep gardens up to 5,000m², with superb grip in its one full test.
The compromise: That test found weak detection of small objects and a strip left at the edges.
Navimow X420 head to head
Head to head
Mammotion LUBA 3 AWD vs Navimow X420
Our verdict: Both suit big, hilly lawns. Pick the X420 if ruts worry you: heise, which has tested both, found its steerable front wheels far gentler in turns. Pick the LUBA 3 if space is tight, because it's shorter, narrower and about 10kg lighter.
Specs
Full specifications
Each specification names its source. Manufacturer claims are not independent test results; unconfirmed figures are labelled.
Owner reviews
Do you own the Navimow X420?
Tell people how it’s held up: cleaning, maintenance, faults and support. Owner accounts are shown separately from independent reviews.
Sources
Where this page’s findings come from
Editorial reviews
- heise bestenlisten: Segway Navimow X420 im Test ↗4.5 / 5Hands-on, Several weeks at home
- inside digital: Navimow X420 im Test ↗Hands-on
- Basic Tutorials: Segway Navimow X420 review ↗Gold AwardHands-on
Sources
- Reddit owner: UK X420 owner review after a LUBA 2 ↗Owner thread
- Segway Navimow: Navimow X4 product page ↗Manufacturer
Videos
- Our French Chateau: We Let a Robot Take Over Our Lawn (Segway Navimow X420) ↗
- Search YouTube for Segway Navimow Navimow X420 ↗Search results may include company demonstrations or similar models. Check the source and model name; a demonstration is not an independent performance test.