Robot vacuums

How high a threshold can a robot vacuum climb, and how to check yours

Published October 26, 2026 · By the BotLineup editors · Prices and specs as of that date, from the pages under Sources

What the climbing figure means

A threshold rating is the height of an obstacle the maker says the robot can drive over. Ask the maker which surface, obstacle shape and test conditions apply to that rating. A rounded oak saddle is easier to climb than a square metal transition strip of the same height. A strip with a gap behind it, or a rug that slides when the wheels push it, can stop the robot well below its rating.

Keep the climbing figure separate from the mop lift figure. ECOVACS rates the DEEBOT T50 Pro Omni to climb 20 mm and lists a 9 mm mop lift. The lift raises the mop pads for carpet. It is not how high the robot can climb.

Robot height is a separate figure again: a taller body affects whether the robot fits under furniture, not whether it climbs a doorway.

How to measure your thresholds and rug edges

Use a ruler or tape with millimeter marks: the ratings here differ by only a few millimeters. Measure from the lower floor to the top of the threshold, then repeat from the other side. The two readings can differ where a doorway joins floors at different levels.

• Measure every doorway the robot needs to cross, not just the one where it stopped.
• For rugs, measure the edge where the robot will approach it, including any binding or fringe.
• Note whether the edge is rounded, sloped or square, and whether a rug edge curls up.
• Write down the tallest number. That is the one to compare.

Then subtract your measurement from the rating. If your tallest threshold is 18 mm and the robot is rated for 20 mm, you have 20 − 18 = 2 mm of margin. That is a thin margin for a square edge. A rounded edge is more forgiving.

Models by stated climbing height

These are the maker's figures, from lowest to highest, each with one store price and the date it was checked. Dyson states its figure in inches and the others state millimeters or centimeters, so the order of the 20 mm group and the Dyson is approximate: 0.8 in is about 20.3 mm.

• SwitchBot K20+ Pro: SwitchBot rates it at 20 mm; $699.99 at the SwitchBot store, checked 2026-10-07.
• SwitchBot S20: SwitchBot rates it at 20 mm; $799.99 at the SwitchBot store, checked 2026-10-07.
• ECOVACS DEEBOT N30 Pro Omni: ECOVACS lists "obstacle climbing up to 20mm"; $259.99 at Walmart and $289 at Best Buy, both checked 2026-10-07.
• ECOVACS DEEBOT T50 Pro Omni: ECOVACS rates it at 20 mm; $399.99 at Amazon, checked 2026-10-13.
• ECOVACS DEEBOT T80 Omni: ECOVACS rates it at 20 mm; $399 at Walmart, checked 2026-10-07, and $549.99 at Amazon (checked 2026-10-13) and Best Buy (checked 2026-10-07).
• Dyson 360 Vis Nav: Dyson rates it at 0.8 in; Dyson's US site listed it as out of stock when checked on 2026-10-23.
• ECOVACS DEEBOT T90 Pro Omni: ECOVACS rates it at 2.4 cm; $499 at Walmart, checked 2026-10-07.
• ECOVACS DEEBOT X11 Pro Omni: ECOVACS rates it at 2.4 cm; $749 at Walmart and $999.99 at Best Buy, both checked 2026-10-07.

20 mm is about 0.8 in; 2.4 cm (24 mm) is about 0.9 in. The ECOVACS and SwitchBot range spans 24 − 20 = 4 mm. For thresholds between 20 and 24 mm, the T90 Pro Omni and X11 Pro Omni have covering ratings. The T90 Pro Omni was cheaper: $499 versus $749 for the X11 Pro Omni at Walmart, both checked 2026-10-07.

Well under 20 mm, all the listed models have covering ratings, so mopping, docks and price can guide the choice. Leave extra margin near 20 mm for Dyson, whose inch figure is rounded to a tenth.

After checking the climbing rating, compare stores for the same model. The T90 Pro Omni was $799.99 at Amazon on 2026-10-13 and $499 at Walmart on 2026-10-07: $799.99 − $499 = $300.99. For those stores and dates, the T80 Omni gap was $549.99 − $399 = $150.99; the X11 Pro Omni gap between Best Buy and Walmart was $999.99 − $749 = $250.99.

When a ramp or a no-go line is the better fix

If your tallest threshold is above every rating you are considering, or only a millimeter or two under it, a small threshold ramp can be the simpler fix. It gives the wheels a slope instead of a vertical edge. Choose one with a low leading edge so the ramp itself does not become the new obstacle, and secure it so it does not slide.

Sometimes the robot does not need to cross at all. A sunken room, a raised bathroom saddle or a thick rug the robot keeps getting stuck on can be kept outside the cleaning route if your model supports no-go zones. Confirm that feature and support for separate maps before relying on either; otherwise, carry the robot across when needed.

If your robot used to cross a threshold and now stops there, check the wheels and the underside before you blame the rating. Hair wrapped around a wheel axle or a dirty drop sensor can make a robot hesitate at edges it once climbed.

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