Review Summary


The Otto weed grinder’s single-button interface makes the process so simple and quick- grinding your herb in a quarter of the time it takes to do it manually. Whether you’re grinding your herbs to vape or to roll the old-fashioned way- this grinder proves useful. The only question is if it’s worth the spend. As a premium device with all these features, it does come with a premium $200 price tag – that’s the price of about 4 good manual grinders.


While vaporizers are quickly becoming more advanced and some are even made smarter with A.I. Some devices are even foregoing on-board temperature controls for smartphone apps to better control. Grinders, on the other hand, have remained mostly manual and electronic grinders have yet to take a strong footing in the market.

This is where The Banana Bros. OTTO grinder (buy on Amazon) comes in. It’s easily one of the best and most impressive automatic grinders you can get.  It features smart grinding technology to precisely measure the weight and consistency of your herb – so the aluminum teeth grinds your herb perfectly every time. On top of that, it also has the ability to fill a paper cone (with that perfectly ground herb) in 5 seconds flat.

At $150, it’s priced much higher than even the biggest grinders. But its features and grind quality might just make it worth it.

Kit and Accessories

Banana Bros. Otto Weed Grinder Cones

Since the OTTO grinder is technically consumer electronics, it makes sense for it to come with a “kit”. Unlike manual grinders which usually come just as they are.

The Otto grinder’s kit comes with the following:

  • 20 Premium Cones
  • A measuring cup
  • cleaning tool
  • O-Funnel attachment and cone holder
  • Fresh seal cone tube
  • USB cable designed for fast charging
  • Snap cap

Design and Features

Banana Bros. Otto Weed Grinder Review

Coming in at 11.5 inches tall- The Otto grinder is larger than anyone would expect. But in no way is it cumbersome or bulky. It sports a sleek minimalist design that makes it quite discreet when posted on a table or shelf. Obviously, it’s the exact opposite of a traditional grinder which pretty much fits in your hand even when in use. But this grinder is just the type you’d probably end up showing off to your friends for a few extra cool points.

The Otto’s best feature is probably how it brings down prep time to zero. The sensors detect and calculate the material’s density and consistency – before bringing it to an ideal grind. All this is achieved just by pressing a single button. It’s powered by a rechargeable battery that lasts about 30 uses a charge and when you do run out, charging time is a quick half-hour.

The grinder itself is only composed of two parts- the top being the main piece with its smart sensors and two aluminum grinder plates and the bottom cone tube or O funnel that snaps onto it easily. That’s all there is to it. For something that brings so much technology into grinding, the Otto grinder remains incredibly simple to use.

OTTO Grinder Cones

Banana Bros. Otto Weed Grinder Cones Package

The Otto grinder’s kit comes with 20 unbleached, translucent cones that fit onto the cone tube perfectly. Though we’d definitely recommend you vape rather than smoke, these cones are a great choice if ever you wanna try out the traditional route once in a while. These cones burn slowly and evenly and have high-quality filters that allow you to use up all your material without leaving a roach behind.

The only downside is that they are quite pricey, once you run out, you can order a pack of 100 OTTO grinder cone replacements (buy on Amazon) for $145.

How to Use

There isn’t exactly a learning curve to using the Otto, but just like any other grinder, you do have to measure the amount of herb you put into it. The measuring cup provided helps determine how much herb you’d need for a full joint, but if you’re vaping, then you can simply adjust accordingly.

With Pre-rolled cones

Banana Bros. Otto Weed Grinder Cone Insertion
  1. Open up the OTTO to expose the grinding chamber.
  2. Place your herb into the chamber and close the OTTO.
  3. Place a cone into the cone tube and attach the tube to the OTTO.
  4. Press the power button to start the grinding process.
  5. Once grinding is complete, separate the cone tube from the OTTO and remove the filled cone.

For Regular Grinding

Banana Bros. Otto Weed Grinder Operation
  1. Open up the OTTO to expose the grinding chamber.
  2. Place your herb into the chamber and close the OTTO.
  3. Attach the O funnel to the grinder and press the power button.
  4. Once grinding is complete, dispense the weed into the receptacle of your choice.

Performance and Ease of Use

Banana Bros. Otto Weed Grinder

At $150, I wouldn’t expect anything less than the best grind quality. Thankfully the Otto’s sensors ensure that you get the perfect grind at each use, with no misshapen pieces here and there. What makes it even better is that it grinds up the majority of the herb with very little leftover – making it one of the most efficient automatic grinders on the market.

While its ability to fill a cone is definitely a great selling point, the Otto is just as perfect for dry herb vaporizers. Grinding equalizes the spaces between the material which makes it easier to vaporize evenly. Vastly improving vapor quality and allowing all those cannabinoids and terpenes to be more exposed to the heat. You also end up wasting less herb since you don’t have to toss out any unvaporized bits.

Since the Otto is optimized for J’s and cones, transferring the herb onto the vaporizer requires an extra step. The large mouth of the O funnel runs the risk of spilling herb everywhere if you’re attempting to directly pour it into the chamber. You’ll have to empty the ground herb somewhere else and then load it onto the chamber. While that might sound cumbersome, it won’t matter so much once you see and experience that perfect grind.

Just like any grinder (at least those without a non-stick coating), the resin will eventually build up and stick to the grinder teeth. So it’s best to do a quick clean after about 2-4 uses and a more thorough clean after 10-15 uses.

Bottom Line

Banana Bros. Otto Weed Grinder Cone Tube

The Otto grinder brings what was once a mostly manual task to today’s A.I powered times. While it does have more perks tuned towards those who smoke – that doesn’t mean it’s not great for vapers too. The simple single-button interface makes grinding incredibly easy for anyone, most especially those with dexterity issues.

However, if you’re a more occasional roller- it’ll serve you well to ask if it’s really worth the spend. At $150, it’s more expensive than even the best manual grinders. Once you run out of the included cones, the replacements aren’t cheap either. But if you’re looking to spend some serious $$$ and are willing to pay for the best grind, by all means- this is the grinder to get.

If you’re still on edge about electronic grinders, there are several manual grinders that also provide that perfect grind- all you need to add is a little elbow grease. Check out our list of the best grinders of 2024 for more.


General Specs

  • Compatible: Dry Herb
  • Released Date: Feb 2021
  • Body Material: Plastic
  • Smartphone App: Yes
  • Vibration Notification: Yes
  • Warranty: 1 Year

Heating Element


  • Battery Capacity: mAh


  • Overall Score: 4.3/5

Purchase Information

Authorized Dealers

MSRP $149
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