Varia RearVue 820 from Garmin: brighter, smarter and now tracking vehicle size

Varia RearVue 820, Garmin’s most advanced rear‑facing radar light to date. It’s a step forward in both visibility and situational awareness for road and gravel riders. The new unit introduces upgraded radar precision, longer battery life and – most notably – vehicle‑size detection. Making it a first for the Varia line.

The Varia RearVue 820 sits at the top of Garmin’s radar range. It combines a more powerful sensor with the brand’s brightest tail light yet. Garmin says the new radar can identify vehicles from over 175 metres away. It can also analyse their lateral movement, speed and size and then assigns a threat level. That can then be displayed on a compatible Edge head unit, Garmin smartwatch or the Varia app.

Susan Lyman, Garmin’s Vice President of Consumer Sales and Marketing, describes the update as a major leap for rider awareness: “Whether cyclists are commuting or training along busy streets, this radar can help them stay more conscious of nearby traffic, especially with new advanced vehicle tracking alerts.”

Smarter tracking: now with vehicle‑size alerts

The headline upgrade is the new “advanced vehicle tracking” system. Alongside the familiar closing‑speed warnings, the RearVue 820 can now classify approaching vehicles as small, medium or large. Garmin says this helps riders better judge the nature of the traffic behind them. Could be useful on rural roads where everything from hatchbacks to HGVs may appear.

The radar also gains a wider field of view, allowing it to detect movement across multiple lanes. Same‑speed tracking returns too. This flags vehicles that sit behind the rider without overtaking; something many users have found particularly helpful in real‑world riding.

For smartwatch users, Garmin is testing voice alerts through its Public Beta program. Which will add another layer of notification beyond the usual vibration cues.

Brighter tail light, smarter brake light

Visibility is another major focus. Garmin claims the Varia RearVue 820’s tail light can be seen from over 2 km away. It also offers four standard modes; day flash, night flash, solid and peloton mode. There’s also the option to create custom patterns in the Varia app.

The brake‑light function has also been refined: the unit detects deceleration and triggers a distinctive flash pattern to alert riders and drivers behind.

Longer battery life and a cleaner fit

Battery life has been extended to a claimed 24 hours in day‑flash mode and up to 30 hours in radar‑only mode. Great for endurance riders and commuters who don’t want to charge daily. Garmin has finally moved to USB‑C charging and the new seatpost mount is designed to fit a wider range of road and gravel bikes.

Varia RearVue 820 Pricing and availability

The Garmin Varia RearVue 820 is available now at £259.99/€299.99. Which makes it a premium safety upgrade for riders who want the most advanced rear‑facing radar on the market.

We are currently testing out some of Garmin’s other Varia and Edge items.