Best self-emptying robot vacuum
Auto-empty docks differ in bag size and how long they last.
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How this page was made: our picks are based on manufacturer specifications (product pages, manuals and spec sheets, all linked below) and aggregated owner reviews. We have not tested these products hands-on, and we do not publish invented test results, scores or star ratings. Read our methodology.
We compared docks on published bag size and days between emptying. This page is based on manufacturer-published specifications and manuals plus aggregated owner reviews; we did not test the products ourselves.
Quick picks
Spec comparison
| Model | Dust bag | Maker-rated interval | Suction |
|---|---|---|---|
| Narwal Flow | 2.5 L | Up to 120 days | 22,000 Pa |
| Dreame X50 Ultra | 3.2 L | Up to 100 days | 20,000 Pa |
| Roborock Saros 20 | See Roborock | Up to 65 days | 36,000 Pa |
| Narwal Freo X Ultra | 1 L | About 7 weeks | 8,200 Pa |
The picks in detail
Narwal Flow
The Narwal Flow lists up to 120 days from a 2.5 L bag.
Pros
- 120 days
- Track mop
Cons
- 95 mm tall
Dreame X50 Ultra
The Dreame X50 Ultra has a 3.2 L bag rated up to 100 days.
Pros
- 3.2 L
- High climbing
Cons
- 2.4 GHz only
Roborock Saros 20
The Roborock Saros 20 pairs 36,000 Pa with a 65-day dock.
Pros
- 36,000 Pa
- Mop removal
Cons
- Shorter interval
Narwal Freo X Ultra
The Narwal Freo X Ultra has a 1 L bag rated about 7 weeks.
Pros
- DirtSense
Cons
- Small bag
Who should buy what
- Empty least often
The Narwal Flow.
- Max suction
The Saros 20.
About intervals
Day ratings are maker estimates; pets and large homes fill bags faster.
Frequently asked questions
Which goes longest between emptying?
The Narwal Flow, up to 120 days per Narwal.
Did you test it?
No. This page uses manufacturer specifications and aggregated owner reviews. See how we research.
Sources
Specifications were checked against the manufacturer pages, manuals and spec sheets below in October 2026. Makers revise specs and sell regional variants, so confirm the exact model number before you buy. We do not list prices because they change daily; use the retailer link to see the current price.
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