At least 12 years ago, I received one of Knog’s Frog rear lights as a gift. Today, the light still works perfectly, but eventually a small tear developed in the silicone band that secures it to the bike. This Spring I got an offer from Knog to test out an updated pair of front and rear Frog lights, which have several new features my old version didn’t have.
The current Frog lights were updated in 2022, and they now use rechargeable batteries. They also have nine different lighting modes and a battery life indicator. The overall body design of the lights didn’t change much, because it’s genius! I’ve had the Frog lights on my commuter bike since early this year, and they’ve proven to be reliable, easy to use, and offer very good battery life.
Knog Frog Lights – Specs and Features:
The first clever thing you notice about the Frog lights is their shape. I think Knog hit on a great design – It’s sleek, lightweight, super easy to install and remove, and can be attached to anything it can wrap around. The bodies come in six different colors, but in the green colorway, you can really see the abstract resemblance to a frog. The lights are also water-resistant to an IP65 rating.
Knog offers a front and rear version, with the front giving off the expected white light and the rear, of course, glowing red. The Frogs’ curved lenses allow them to throw light to the sides, increasing their visibility from different angles. The Frogs recharge via a USB-C cable, which is not included. The front light claims up to 80 hours of runtime, while the rear lists up to 60 hours.
The Frog (front) weighed in at 20g on my scale. The rear light actually weighed 19g.
Operation/Charging:
The Frog’s one-button design keeps things simple. A long press turns the light on or off, and while illuminated, short presses scroll between a variety of lighting modes, including steady, flashing, and several variations in between. You can also check your battery life when the light is not in use with a quick tap of the button.
Also, whenever the Frog is turned off, its lights flash a few times to indicate battery life. A full charge will light up the whole width of the light’s lens, but as the battery depletes, the LEDs will show how much charge remains from left to right.
I fully charged both of my Frogs from just three LEDs lit on the left side. In just under two hours, both lights were fully charged, so I’d estimate a full charge from completely dead might take roughly 2 ½ hours.
Ride Impressions – Front Frog:
While the Frogs are small, we cyclists know that any light makes a huge difference to our visibility in dim or dark conditions. Even in the daytime, a light will still make you more visible to motorists and pedestrians. The Frogs are easily bright enough to be seen from a good distance away in any light mode you choose, but their nine modes do offer dimmer and brighter options.
I was surprised to find the front Frog does throw some light. In the brighter of the two steady modes, the Frog will light up a small patch of ground ahead of your bike. That said, the Frog is a light that helps you be seen, not a light that helps you see. With a 40-lumen max output, it’s not a substitute for a headlight that actually projects. On a very dark road, I could not effectively see where I was going with just the Frog.
The various modes on the front light might come in handy for off-bike use (clipped to a backpack, perhaps?), but personally, I find riding in anything other than the high or low steady modes distracting and annoying! A bright, flashing light on your handlebars is hard to ignore.
I discovered one bonus with the front light’s steady high mode – It’s bright enough to be useful as a small flashlight around the house. I’ve used mine several times for household purposes!
Rear Frog:
The rear light is easily visible from very far away, and the flashing modes particularly improve your visibility to motorists. I ran the rear light in various flashing modes, but you can choose low and high steady modes as well. The rear Frog offers one extra bright flashing mode that likely affords the best visibility. I was surprised to read that the rear Frog’s output maxes out at 20 lumens, as this mode would be easy to see from a very long distance, even in broad daylight.
I never got the Frogs totally drenched during my testing, but the rear definitely got splattered with tire spray on a few rides. It survived the moisture just fine, and ultimately, both of my Frogs have performed without fault all year.
Since the Frogs are so easy to install and remove, that means they’re easy to steal. If you live anywhere aside from a small, friendly town (like the one I’m lucky to call home), you will want to pull the Frogs off your unattended bike so no one else does. Luckily, they’re super easy and quick to remove and install.
Battery Life:
As for the Frogs’ battery life, I didn’t attempt to track 60-80 hours of use, but I have determined that not every mode will last that long. Riding with the front light in the brighter steady mode will definitely not provide 80 hours of runtime, but I suspect certain flashing modes would get much closer or reach the claimed run times. Even in high steady mode, the Frog lasted for many rides before needing a charge.
It seems the runtime on the rear Frog is slightly less than the front, as advertised. I ran the rear in various flashing modes, and it drained at a similar rate to the front light running between high and low steady modes. Again, battery life is still very good; Even with daily use, you’ll likely go weeks between charges.
I also found out the Frogs’ batteries do not lose their charge quickly when sitting around. While I tested two e-commuter bikes with their own integrated lights, the Frogs mostly sat for about five months this summer. Seeing very little use during that time, both retained ¾ of their battery life from my initial charge.
In mid-September, I recharged both Frogs to full power. Neither were actually dead yet, I just topped them up for Fall riding. It’s now mid-December, and I’ve been riding my commuter bike more often in recent weeks. My commuter rides tend to be short, but currently, both batteries still have at least 25% life left in them. Leaving the Frogs in my cold shed doesn’t seem to impact battery life much, which is great.
Pricing:
Knog’s Frogs are a high-quality alternative to the cheaply made copies you could buy through massive online retailers… and likely toss in the garbage after not long. I’d wholeheartedly recommend spending a little more and enjoying proper product quality!
The Knog Frog lights are available in six different colors and come with a two-year warranty. MSRP for the Frog front/rear set is normally $55, but currently, they’re on sale on Knog’s website for $41.
