The Best Rear Bike Light 2021

Whilst cycling at night, a rear bike light is an essential piece of kit that’s also a legal requirement in the UK. Within this article, we roundup the latest models that provide ultra bright light, a long battery life and multiple lighting modes.

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Best Rear Bike Light
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The best rear bike light is the CatEye Rapid X3, which provides an impressive light output of 150 Lumens for clear visibility at night and daytime. If you are on a tight budget, the GuardG3X is the best option.

Rear Bike Light Comparison

Rear Bike LightLumensMax Battery Life
CatEye Rapid X3150 Lumens30 Hours
GuardG3X100 Lumens12 Hours
CMeilan Smart50 Lumens50 Hours
Knog Blinder44 Lumens30 Hours
Joyfulbid LED20 Lumens56 Hours
CatEye Omni30 Lumens200 Hours

Not only is it unsafe to not use lights on your bike at night but it’s also illegal in the UK. Considering the low cost of rear bike lights, it’s worthwhile investing into a high quality light that will last for many years.

Below is a list of the rear bike lights that provide multiple lighting modes and ultra bright light for maximum visibility.

The Best Rear Bike Light

1. CatEye Rapid X3 Rear Bike Light

CatEye are a brand that produce a wide variety of bike lights and this Rapid X3 model is their flagship rear light option. It’s powered by a rechargeable battery and features twin COB LED strips that output up to 150 Lumens.

In terms of mounting the light, it can be attached using the integrated rubber band, which is ideal for seat posts or trays.

Other features of the CatEye Rapid X3 include:

  • Light output of 150 Lumens
  • USB rechargeable battery (3 hours to full charge)
  • Mounts via a rubber band
  • Low level battery indicator
  • Choice of six different flash modes
  • Longest lighting mode provide up to 30 hours run time

For those that are looking for the best performance, the CatEye Rapid X3 certainly ticks that box. It’s the brand’s new and improved version that includes an impressive 50 Lumens more light than its predecessor. This makes a huge difference and makes it the perfect rear bike light for daytime or night use.
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2. GuardG3X USB Rechargeable Rear Light

The GuardG3X is a high powered yet affordable rear bike light that’s by far the most popular in the UK. It uses a super bright COB LED strip that outputs up to 100 Lumens, which is more than ideal for night or daytime use.

It’s a versatile light that can be mounted to the rear of your bike or helmet and also has the choice of six settings to ensure you are visible on busy roads.

Other features of the GuardG3X Light include:

  • 100 Lumens
  • Choice of six light output modes
  • Fully recharges in just 2 hours
  • 12 hours of battery (lowest light setting)
  • IPX3 waterproof rated
  • Weighs just 1 LBS
  • Wide beam pattern
  • Supplied with a carry pouch

To install the light to your bike or helmet, it comes with 8 mounting rings in four different sizes that fit bars up to 45 mm.

Overall, the GuardG3X is by far the best rear bike light for the money that combines performance with affordability. It provides a long lasting run time and ultra bright light for clear visibility at night or the daytime. Due to the low cost, you could even buy two for both the helmet and rear of the bike for maximum visibility.
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3. CMeilan Smart Bike Tail Light

One of the most advanced rear bike lights in this article is by the CMeilan brand and it includes both a brake and light sensor. It has an integrated accelerator that triggers the brake sensor whilst braking, which has the effect of outputting additional light to warn people behind for extra safety.

It’s also built to the highest of standards with a durable aluminium alloy and stainless steel construction. According to the brand, it has a waterproof rating of IP65, which is far better than many similar priced alternatives.

Other features of the CMeilan Smart Light include:

  • Light output of 50 Lumens
  • Intelligent brake sensor
  • Automatic light sensor
  • IP65 waterproof rating
  • Mounts via the supplied bracket
  • Choice of 4 lighting settings
  • Provides up to 50 hours of run time
  • Fully recharges via USB in 2 hours
  • Battery level indicator

Considering the amount of technology and the superior build quality, the CMeilan Smart Light is one of the best rear bike lights on the market. It’s also backed by a two year warranty for complete peace of mind.
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4. Knog Blinder Mob Rear Bike Light

The Knog Blinder is a premium rear bike light that’s designed for standard and aero bike posts. It’s a well-built light that has a reflective face and a light output of 44 Lumens, which can be controlled by six different light modes.

Other features of the Knog Blinder include:

  • Compact design (5 x 9 cm in size)
  • Light output of 44 Lumens
  • Reflective face
  • 5 different light settings
  • 1,000 metre visibility range
  • Rechargeable via USB

Although expensive, the Knog Blinder is built to the highest of standards with a high quality look and feel. The brand also offer a matching front bike light, which has the same high quality and compact design.
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5. Joyfulbid LED Rear Bike Light

The Joyfulbid bike light is a compact yet ultra bright option that fits 20 to 28 mm tubes but can be installed to many other locations. It also provides the option to choose between 5 different lighting modes to best suit your requirements.

Other features of the Joyfulbid Compact Light include:

  • Compact design (4 x 4 cm in size)
  • Light output of 20 Lumens
  • Max runtime of 56 hours
  • Recharges in 2 hours
  • Durable ABS plastic construction
  • Dust and water resistant
  • Soft elastic strap for mounting

If you require a small rear bike light that provides adequate light output, this compact design is the best option. Compared to similar priced alternatives, it offers far superior quality and far more lighting modes.
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6. CatEye Omni Triple LED Light

Another rear bike light by the reputable CatEye is the Omni model, which is one of the cheapest lights on the market. It uses a triple LED that provides all-round visibility and a light output of 30 Lumens.

Unlike many of the alternatives that are recharged via USB, this rear bike light is battery powered and uses three AAA batteries, which may be more desirable for some cyclists.

Other features of the CatEye Omni include:

  • Triple LED configuration
  • Opticube lens technology
  • Three lighting modes
  • Runtime of up to 200 hours
  • Flex bracket or belt clip for mounting
  • Matching front light available

The CatEye Omni is an excellent all-round option that’s cheap and backed by the reputable brand for peace of mind. It may not be as bright for daytime use but it’s more than ideal for clear visibility at night.
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Rear bike lights are an essential piece of equipment for those that cycle during the night and require additional visibility. All of our recommendations are designed to easily mount onto any type of bike and also provide adequate light output. Considering the affordability of most lights, we strongly advise spending slightly more for a far higher quality light.

The Author Who Worked On This Article

author dan darimo

Dan Morgan

As a keen DIY’er, gardener and somebody that loves the latest tech, Dan is someone that brings years of experience in multiple trades. Since buying his first house, he has been obsessed with renovating properties and filling it with the latest products. This has led him down the road of testing hundreds of products and creating in-depth “how-to” and informative guides that offer his first-hand experience. Other interests include working on cars, keeping fit through sports or his home gym, caravanning and drinking great coffee.

If you would like to read more about Darimo and the authors, you can visit our about page. This goes into great detail regarding how we test products, create our guides and everything else.

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