In two completely independent tests in 2026 — conducted by Villanytt and Bäst i Test Guiden — the Swedish-developed rat repeller Repello was named the winner of the year. This makes Repello the only rat repeller on the market to receive top marks in multiple separate tests, and the only one verified in a scientific study at the Swedish University of Agricultural Sciences (SLU).
Ultrasonic repellers have been around since the 1980s, but the technology has long been controversial. The Swedish Consumer Agency (Konsumentverket) was early to criticize these products for lacking evidence, and several models were pulled from the market when manufacturers couldn't prove they worked. Throughout the 1990s and 2000s, organizations like the Swedish Villa Owners' Association continued to scrutinize the market, branding many models as outright scams.
Time and again, tests showed rats and mice simply ignoring the sound. The 2025 tests confirm the picture: most rat repellers don't work at all. Except one.
Why Repello was Top-Ranked 2026
- The only rat repeller with documented effectiveness across multiple tests
- Patented ultrasonic technology based on LTU research — 94–100% effectiveness in SLU's independent field study
- Top results in all main categories at Villanytt & Bäst i Test Guiden
- Instinctively avoided by rats due to its nature-mimicking alarm signal technology
Repello — the only rat repeller with documented effectiveness
In both Villanytt's and Bäst i Test Guiden's evaluations, the pattern is clear: Repello is the only model to demonstrate actual impact on rodent behavior.
The technology is built on years of research into ultrasound effects on mammals, where Professor Örjan Johansson identified the warning signals rats use in nature. By recreating these dynamic ultrasonic patterns, Repello creates a sound environment that rats instinctively avoid.
This was confirmed in a pilot study at the Swedish University of Agricultural Sciences (SLU), where the effect was measured under controlled conditions.
Repello takes first place in two independent tests
Villanytt: "The most effective rat repeller on the market."
The test highlights:
- The only repeller with documented scientific effectiveness
- Achieved 100% effectiveness in SLU's tests
- Wide coverage and easy to install
(Source: Villanytt – Bäst i test råttskrämmor 2026)
Bäst i Test Guiden: "The only rat repeller with measurable and reproducible effectiveness."
The panel highlights:
- Top results in all main categories
- Consistent and repeated effectiveness across different room types
- Noticeably better than traditional models that emit static tones
(Source: Bast-i-test.se – Musskrämma & råttskrämma 2026)
Having two separate testing organizations reach the same conclusion is rare — and telling.
SLU's scientific test: 94–100% effectiveness Perhaps the most decisive piece of the puzzle is the SLU study, in which researchers tested Repello in environments with established brown rat populations.
The results:
- 94–100% reduction in activity while the device was running
- In several test areas, not a single rat was observed during the entire period
- Activity increased immediately when the unit was switched off
- Rats avoided corridors and surfaces where the signals were strongest
- The response resembled a flight reaction, not merely irritation
This makes Repello the first rat repeller in Sweden to ever achieve complete effectiveness in an independent scientific test.
Conclusion: Repello is the obvious test winner of the year
The 2026 tests show larger differences than ever before in the rat and mouse repeller category.
- Most models lack proven effectiveness
- Many rely on outdated technology with no scientific basis
- Repello is the only product with documented, repeated and reproducible effectiveness
With both Villanytt and Bäst i Test Guiden naming the same product the winner — while SLU has demonstrated 94–100% effectiveness — the choice for consumers has never been clearer.
