Otto Grinder Review: The Fastest Automatic Blunt Roller


by Thanush Poulsen

Updated: October 26, 2020

Otto Grinder desktop

Review Score: 83/100

Price Range:
about 20-30 rolls on each charge
Cone Roller:
Seal Cones:
USB Chargeable:
Works with:
  • Herbs icon


  • Good for marijuana, tobacco, and other dry herbs
  • Grinds the herbs to an ultra-fine consistency
  • Rolling blunts is easy


  • Very expensive grinder
  • Requires frequent cleaning

Starting Price: $ 199

The Otto grinder for dry herbs by Banana Bros is a single button-operated device that uses SMART grinding technology to precisely measure the herbs’ consistency and grind them to perfection.

Another advantage that this device offers it an all-in-one auto cone roller that is spill-free. Metal teeth are used to grind down the herbs, and they hold together well without chipping or wearing down.

Finally, it is USB chargeable, making recharging easier and faster than in other grinders.

Otto Dry Herb Grinder Performance

There is no need to adjust the settings because the device does it automatically thanks to built-in sensor technology.

This feature simplifies usage immensely, making it perfect with dexterity any issues.

Press the activation button, and the Otto will do all the work.

The Otto and its cones are useful for blunt smokers and vapers. In either case, the herbs are prepared in a manner that makes them suitable for either method of use.

This is especially the case for vapes because the fine grind allows for more surface area in the heating chamber to be used. The fine texture of the weed makes for an even burn while it is in the joint.


What everyone is going to like is that the device is fully compatible with marijuana, smoking tobacco, and various types of dry herbs. The versatility of this unit makes it a true and proven all-in-one device.

Thus far, the device has held up very well, and there have been no issues with it breaking or parts needing to be replaced. It is well built and meant to last. Even though it is quite expensive, the level of performance makes the extra cash well worth it.

The Weed Grinder Kit

The kit comes with the grinder, o-funnel, and the fresh seal cone tube. Additionally, it comes with a measuring cup and over 20 grinder cones. A four-in-one tool is there for cleaning, and a USB cable is included for charging.


Otto Grinder and Roller Build Quality

The Otto grinder might be large, but its sleek and ergonomic design makes up for its size. Additionally, it has a lot of features other devices lack, including the joint roller, resulting in faster than average preparation time.


The Otto also uses sensors that adjust according to what is inside the grinder. These sensors allow preparing the weed without having to make adjustments beforehand.

This device is not only simple to use because of its sensors, but the two-piece design makes taking it apart and putting it back together again easy — the o-funnel and cone tube snap-on without any difficulty.

Otto Automatic Grinder Battery

The device is powered by a built-in lithium-ion battery that can handle 30 blunts per charge. There are a lot of interesting features in this grinder, but the coolest is that it has wireless charging.

Traditionalists can recharge it by plugging it into a wall socket, USB port in a computer, or a car charger while on the go.

Using the Grinder

Using the Otto is simple.
The kit comes with a measuring cup, so determining how much weed is needed for a joint or bowl is not hard.
Measure out the pot, or whatever loose leaf is to be used, place it in the grinder, and then hit the power button.

To roll a blunt

  1. open the device and expose the grinding chamber
  2. when it is fully open, place the weed inside and close it
  3. take the cone, put it onto the cone tube, and attach it to the Otto
  4. once the cone and tube are connected, press the power button to start grinding the herbs
  5. when the device finishes grinding the herbs, remove the cone tube
    and the joint is ready for use


For regular grinding

  • open up the Otto and put the herbs into the chamber
  • close the grinder and attach the o-funnel and press the power button
  • allow enough time for the herbs to prepare
  • then remove the finished product

    Otto Automatic Joint Roller

    Blunt rolling is done extremely fast, reducing preparation time to seconds instead of minutes. No pre-rolling of the joints is needed. The Otto does everything.

    Not only does it roll the joints, but it does so in a manner that ensures that the herbs burn perfectly. On the inhale, the join will not burn unevenly, and each drag will be smooth as a sheet of ice. Also, the paper will not unravel, making each smoke session frustration-free.

    How to Clean

    Like all things mechanical, Otto needs to be cleaned periodically. Residue from the herbs builds up in the chamber, teeth, and the gears quickly, which results in herbs that do not grind as well as they should.

    But, cleaning is easy thanks to the four-in-one cleaning tool in the accessories. Take the aluminum plates off and soak them in a cleaning solution, and use the cleaning tool that comes with the kit to remove the resin.

    The Otto should be cleaned every three uses to ensure that the herbs grind to the perfect consistency. Every ten uses, take it apart and then do a deep, thorough cleaning using alcohol or alcohol-free solution.

    Otto Grinder Specifications

    Cone Roller: Automatic
    Patented Sensor Technology: Yes
    Seal Cones: Transparent
    Odor-Resistant Construction: Yes
    GMO and Animal Product Free Cones: Yes
    USB Chargeable: Yes

    Pros and Cons


    • Good for marijuana, tobacco, and other dry herbs
    • Grinds the herbs to an ultra-fine consistency
    • Rolling blunts is easy
    • No adjustments needed thanks to its built-in sensor technology
    • A powerful battery that is good for 30 uses


    • Very expensive grinder
    • Requires frequent cleaning
    • More cost-effective options are available for vapers

    The Otto Dry Herb Grinder: Final Thoughts

    The Otto grinder by Banana Bros is an excellent buy for rolling blunts, but it also grinds herbs well enough so that they can be vaped, too. The joints are rolled to perfection, and the herbs are ground to an excellent consistency.

    For vapers the Otto grinder is a treasure as it provides the most cropped and still flavorful pieces, though.

    Please let us know your thoughts about the inner workings of the unit, how well it grinds the herbs, or anything else you think is important.

    Published: May 22, 2020Updated: October 26, 2020

    Thanush Poulsen

    Being a regular Sweden student, I discovered innovative ways of living healthier. And with my very first e-cigarette, I’ve got obsessed with all things digital. So vaping collided my interests in electronics, science, and health. I enjoy bringing people into the world of vaping through my reviews, guides, and best-of lists.


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