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The Best Ultrasonic Cleaner for Delicate Clothing

The Best Ultrasonic Cleaner for Delicate Clothing

Dolfi is a small, portable ultrasonic cleaner for delicate clothing. The device aims to replace hand-washing for textiles, and to provide a much needed solution for laundry on travels. It isn’t meant to be a permanent replacement for washing machines.

Dolfi’s name is actually a tribute to Dolphins, since they’re the most advanced users of ultrasonic technology. The crowdfunding campaign for this product has been widely successful, and a portion of that money was reserved for dolphins research and welfare.


Dolphin jumping out of the water



  • Gentle on fabric
  • Small and portable
  • Simple to use
  • Quiet operation
  • Safe to use
  • Saves energy and water


  • Not useful for larger loads

Does Dolfi Really Work?

Short answer: Yes, it does!

Ultrasonic technology has been used for cleaning since the 50s. It became widely available for medical and industrial applications to clean small, intricate objects and to accelerate surface treatment processes.

Dolfi had a working prototype since 2015, and was distributed among beta testers in 2017.

Since then, thousands of devices have been shipped all over the world.

It may look like magic, but the science behind it is actually well-understood.

What Is an Ultrasonic Cleaner?

Ultrasonic cleaning is a cleaning method that uses sound waves that are beyond the human hearing (above 20KHz). The sound waves agitate the water in a process known as “cavitation”.

This process creates millions of tiny bubbles that implode creating a vacuum in the water and the jet stream created frees the dirt from deep in the fabric.  This is what makes ultrasonic cleaning so effective for washing deep into the fabric where hand washing cannot.

It also works as a mechanical disinfectant against bacteria.


Cavitation Process


What Are Some Alternative Uses for Ultrasonic Cleaners?

Besides cleaning fabrics (which is what Dolfi is meant for), ultrasonic cleaners have been used to clean luxury items such as jewelry, glasses, watches, coins, and fountain pens. It’s also been used to clean laboratory, dental, and surgical instruments due to its disinfectant properties and hands-free mechanism.

Ultrasonic cleaners can wash many objects, including musical instruments, phonograph records, electronic equipment, guns, fishing reels, golf clubs and so on.

Basically, anything that has a lot of delicate parts that can be damaged with manual washing, and also has many crevices that are difficult to reach.

Dolfi can wash some of the items here that aren’t clothing, as long as they’re small and lightweight, like for example the glasses or sunglasses.

What Frequency Do Ultrasonic Cleaners Use?

Ultrasonic cleaners use a frequency range above 20KHz, which is inaudible to the human ear.

The higher the frequency used, the smaller the cavitation bubbles created. Small cavitation bubbles are good for gentle cleaning and for getting into smaller crevices.


Deep Cleaning of ultrasonic technology


How to Use Dolfi?

Using Dolfi is really simple. All you need is water, a waterproof container, detergent, and a power outlet.

You need to have a large container and enough water to allow the cloth to float freely, this creates the best condition to remove the contamination. The recommended ratio is 5 liters of water for every one pound of laundry.

The water should be around 30-40 °C. It should be warm, but not too hot. High temperatures can damage delicate fabrics.

The reason the water has to be warm is that ultrasonic waves travel faster in warmer water, not to mention that it makes cleaning easier.

A ceramic or metal container is better than plastic at reflecting the ultrasound waves, but any waterproof container will work. The easiest container to find is the average kitchen or bathroom sink.

For best results, place the Dolfi device at the bottom of the sink with the logo facing upwards. Make sure there’s at least 5 centimeters of water between the device and the clothing, and that the clothing is floating freely above.

The device itself is very quiet, so you won’t know if it’s working from the sound alone. There are 6 blue lights that indicate how long its been working (each light is for 10 minutes of operation). Most stains should be gone within 30-40 minutes, but you can leave them for a whole 1-hour cycle.


The 4 steps to using Dolfi


Is Dolfi Portable?

Yes! Dolfi is a small device that fits into the palm of your hand.

Because it’s specifically designed for traveling, it comes with interchangeable plugs to match the outlets of different countries you may find yourself in.

Does an Ultrasonic Cleaner Need Detergent?

For the most part, yes. A mild detergent is preferred, especially since you’ll most likely be using Dolfi to wash delicate fabrics.

However, any kind of detergent would work, whether liquid or powder. A higher-quality detergent would ensure better results. 

If you’re washing swimwear, you don’t need to add detergent. Ultrasonic cleaning is effective at removing chlorine and sea salt from cloth with water alone.

If you’re washing an object that isn’t clothing, you have to use a detergent that’s appropriate to the object being cleaned and the type of stain you’re trying to remove. Never use flammable solutions.

How Much Laundry Can Dolfi Wash in One Load?

Dolfi can wash up to 1 Kg of clothing in every load and you’ll need at least 10 liters of water to fit that load. The clothing must be floating freely and have a distance of at least 5 centimeters above the device.

Isn’t It Dangerous to Plug the Ultrasonic Cleaner into the Outlet and Put It in the Water?

Not at all. It may seem counter intuitive to plug the device into an outlet, then place it inside the sink, but it’s totally safe!

Dolfi is housed inside a smooth plastic casing that is waterproof, and the wire itself is flexible and waterproof as well.

The main function of the device requires it to be placed inside water, so it has been tested numerous times for safety. It has been developed in accordance with international standards for electrical devices that work underwater.

If you’re still concerned, it helps to know that there’s only 12 Volts going through the cable at any given time, same like in your trimmer or toothbrush.

Is Dolfi a Replacement for Normal Washing Machines?

No. Dolfi is designed for small loads, with a maximum of 1.5 Kg. Even if you’re using the maximum capacity, you still need enough room for the clothing to float freely, so it’s not convenient for larger loads.

Dolfi is more suitable for the kind of objects that are too delicate to be put in the washing machine. Any heavy laundry such as linen and towels wouldn’t work.

Dolfi is more efficient than washing machines for small loads, in fact it uses up to 80 times less power, and 12-15 times less water every time you use it instead of switching on the washing machine.



If I’m not Traveling, How does Dolfi Help Me?

Dolfi is a lot gentler on your clothing than a washing machine, and uses significantly less power and water to wash them. It’s also much easier to use and quieter (in case you need to wash something at night).

When not traveling, Dolfi is a great alternative to hand-washing. You’ll have more time to do other things and won’t risk ruining the fabric with mechanical force of the washing machine drummer.

What Kind of Clothes Does Dolfi Wash?

Unfortunately, Dolfi isn’t meant for all kinds of fabric. For best results, make sure the item you intend to wash falls under one of these categories:


  • Delicate fabrics, such as silk, chiffon, lace, and so on. Any fabric that you’d be too afraid to put in the washing machine
  • Clothes that are tagged “hand wash only”, but that are not damaged from water alone (i.e. no leather!)
  • Shaped apparel, such as hats, corsets, dresses, or bras
  • Performance outfits, like figure skating and dance costumes
  • Swimwear
  • Activewear, such as yoga leggings, cycling outfits and other high performance training apparel
  • Garments with applications, such as buttons, studs, gems and so on
  • Children’s clothing


It’s not recommended to use Dolfi to wash any of the following:


  • Large or layered fabrics, such as sheets and towels
  • Heavy stains, such as motor oil
  • Jeans
  • Large knitted items

What Kind of Stains Can Dolfi Remove?

Dolfi is great at removing everyday stains, such as dust, blood, sweat, different oils, and many beverages including red wine, coffee, most juices, and cocoa. Dolfi is good at removing odor and will leave your clothes feeling fresh.


before and after


It’s also exceptionally good at removing chlorine and sea salt from swimwear, and doesn’t even need detergent to do so.

Some stains may need pre-treatment before washing with Dolfi, such as food stains that have a large particle size. For those cases, use a detergent enhancer or stain remover and give it a rinse before using Dolfi.

For really dirty clothing and heavier stains (such as motor oil), Dolfi isn’t recommended.


What Are the Different Types of Ultrasonic Cleaners?

Ultrasonic cleaners can be divided into several types based on their size and capacity.

Large Capacity Industrial Ultrasonic Cleaners

These ultrasonic cleaners have tanks that generate ultrasonic frequencies between 25Khz and 40KHz, which means they’re better suited for solid objects and machine parts. They can also be used for automotive parts and large musical instruments.

Table-top and Bench-top Ultrasonic Cleaners

Table-top ultrasonic cleaners can range in size and capacity. They often operate on a frequency of 40KHz, which is very versatile. The larger ones can be used for cleaning machinery, while the smaller ones are great for small machine parts, surgical instruments, optics and lenses, and so on.

Portable Ultrasonic Cleaners

These consumer-friendly devices are designed for every day, non-industrial uses. They often reach frequencies higher than 40KHz and can be used to clean jewelry, vegetables, clothing, glasses, watches, and the like. These cleaners are typically sold as a compact device without a tank. Dolfi is a pioneer of this category.


Dolfi is an innovative solution that utilizes technology to solve an everyday problem. It’s a perfect travel companion and a handy tool to own when the washing machine seems too aggressive or simply not available.

Dolfi isn’t meant to be used as a replacement for washing machines, but rather as a lighter, more portable companion. It can be considered a replacement for hand-washing.

Dolfi Ultrasonic Technology Keeps Your Activewear at Peak Performance

Dolfi Ultrasonic Technology Keeps Your Activewear at Peak Performance

Activewear has come a long way from the days of a traditional tracksuit. 

Now the items you use for crossfit, yoga or cycling are all state of the art pieces of textile created and designed in laboratories after years of research and experimentation to bring us the best performing activewear. 


Not just to keep us warm and comfortable but to even improve performance.  A study published by the AUTEX Research Journal goes deep into what it takes to produce activewear that gives you the edge.  It mentions applications like nanotechnology, UV protection, anti-bacterial fabric and anti-static microfibers with complex fabric structures, all designed to help you perform at your best, every time.

Can't we just wash our gym clothes in the washing machine?

After all that development and technology to make the best piece of clothing possible we just throw them in the washing machine when we’re done.  While washing machines are another great invention, they can damage your perfectly designed leggings and cause them to lose that extra quality that you paid for when picking them out.



When you throw your sportswear in the washing machine and give it a spin cycle the damage to those fabrics is irreversible.  So after a short time, you need to go out and buy some more. 

Not to mention the cost of running the washing machine after every session.  Not only are you using electricity to power the washing machine, but a typical washing machine will also use anywhere from 70 to 120 liters of water in a single wash cycle.

What if there was a way to deep clean your gear after every use and never risk damaging those complex fabric structures? Save money and have a lower carbon footprint?   Well, ultrasonic technology is the answer!


What is Ultrasonic Technology and How Does it Work?

Put simply, ultrasonic technology can be applied to cleaning fabric because of the cavitation phenomenon. The ultrasonic devices have a transducer inside that converts electric power into a range of sound waves. These sound waves create rapid changes of pressure in the water and this generates millions of tiny bubbles. 

These bubbles then implode creating micro-jetstreams of water (mixed with detergent) that dislodges the dirt from deep inside the fabrics.  This activity allows for the washing of textiles without traditional mechanical rubbing and it is a perfect alternative to hand washing. 

Industrial ultrasonic cleaners have been using this technology for years to clean mechanical components, surgical instruments, human body implants and other items that would get damaged in other processes, but now this technology is available for you at home so you can take care of your sportswear.




A Use Case for Dolfi

Activewear is a broad concept, let’s take a look at one specific use case:  Swimwear.

Whether you’re chasing a wave or doing laps of the pool, your swimwear takes a lot of punishment.  Swimwear applies all those state of the art designs and technologies to produce fabric and shapes that work with you so they don’t slow you down.

Yet the first thing you and I do is expose them to saltwater or chlorine filled swimming pools.  Then what do you do?  You rinse them off under the tap and leave them out to dry because you need them again tomorrow. You’re not alone.  We all do it.  But saltwater and chlorine remain deep in the fibers and slowly weakens the fabric and it eventually loses its integrity.



Washing your swimwear with Dolfi means not only you do not need aggressively rub it to get it clean, it cleans at a microscopic level to ensure there is no trace of saltwater, chlorine or even bacteria that always gets trapped.

So when you get home from your next trip to the beach or swimming pool just drop your swimwear in the sink filled with warm water and leave it to Dolfi to rinse them.  You don’t even need detergent.

When you want to give them a complete clean before storing them away, by all means you can use some detergent with Dolfi.  But when you’re just looking to get the chemicals and bacteria out of your swimwear there’s no better ally than Dolfi.




What are the benefits of using Dolfi to clean and protect your activewear?

As we’ve learned, the process of ultrasonic cleaning is very delicate on fabric since there is no rubbing, twisting or stretching of the items.  So your favorite technologically designed sportswear will last much longer and keep performing at it best.

Using the Dolfi device only requires 5 to 10 liters of water instead of the 70 to 120 liters a washing machine will use whether it’s a full load or just you gym gear.

The Dolfi device uses around 80 times less energy than a traditional washing machine.  While the Dolfi device does not fully replace your automatic washing machine, it’s there for your small washloads and quick gentle refreshment of your daily items. It will reduce the number of times you turn on your washing machine, saving water, energy and your special clothing.

It’s very simple to use.  Just fill the sink or any basin with 5 to 10 liters of warm water (about 30°C)

Put your Dolfi device at the bottom of the sink and make sure there are approx.. 5 cm of space between Dolfi and your clothes so the tiny bubbles can do their thing. 



You can set and forget.  Hand-washing is not only damaging to delicate fibers, it also requires you to be there actively washing the items.  Since the Dolfi does all the work, you can set it and go do something else.  You just gained an hour back.  The device turns off automatically when the cycle is completed, so you just need to hang out to dry once you're back and you are done!



Do you have some activewear that you could use Dolfi on?  Check out the full specs here.  Your training clothes will thank you.

How to Use Dolfi - AKA The Holy Grail

How to Use Dolfi - AKA The Holy Grail

We created this How to Use Dolfi guide with everyone in mind. Whether you’ve just received your brand new, ultra-sleek device, you’ve had it for a while or you’re looking into getting your very own Dolfi - these tips will guide you through the entire process of using your Dolfi for optimal results, which will prevent any technical glitches from shortening the life of your new best friend in laundry. 

What types of clothes Dolfi is designed for:

Your next-gen washing device is not meant for all types of fabrics. Here are the items Dolfi is ideal for and will deliver the best results: 

  • Clothes made of delicate materials such as silk, chiffon, moire, most sheer fabrics, lace, cashmere, and mohair
  • Clothes that are originally meant to be hand-wash only but are not damaged from contact with water alone like leather pants
  • Shaped apparel (dresses, bras, corsages, and hats)
  • Fashion with applications like buttons, studs, jewellery and more 
  • Delicate lingerie and undergarments 
  • Activewear like leggings, sports bras, sport shirts, sport socks and trainers
  • Swimwear 


    Lace is a perfect example of a fabric that Dolfi is great at cleaning

    What types of clothes are NOT recommended to wash with Dolfi 

    If you want to get the best results for your laundry, then you should take note of the clothing items that won’t work well with Dolfi. These are: 

    • Big volume laundry items like bed linens or towels
    • Working clothes with heavy duty dirt, like engine oil 
    • Jeans  
    • Large knitted items like blankets and big ol’ jerseys (sorry granny!) 


      The perfect water conditions for Dolfi 

      Achieving perfect water conditions is about the single most important thing to keep in mind when using your device. Water is the medium that creates the necessary conditions for the ultrasonic energy to do its cleaning magic and radiate its power. A low amount of water reduces the size of the active ultrasonic energy field and diminishes the cleaning results. You need enough water in the container to allow your clothes to float freely thus creating the best cleaning conditions. 

      It’s important to ensure that your Dolfi is never switched on and running outside of water. Pay close attention to the water level and make sure the water doesn't drain from the container during the wash cycle (Your Dolfi Sink Plug will help with this). These points are extremely important as both situations can lead to the device overheating.

      How much water do I need? 

      The more water you have around the fabric and device - the stronger the cleaning possibilities and results. We don’t mean that you need to head out to the swimming pool to wash your favorite threads - only that you need about 5-10 litres of lukewarm water for 1-2 pounds of laundry. 

      Water temperature 

      The water temperature should be around 30-40 degrees °C (86°F - 104°F). It should feel warm, but not burn to the touch. If the water is too hot, it can damage your delicates, especially woven ones.

      What container do I need?

      Dolfi should be used in a waterproof container. Hard materials, such as ceramic or metal, reflect the ultrasonic waves a bit better than plastic. Using it in your standard bathroom ceramic sink is perfect. 


      A standard ceramic bathroom sink is the perfect container for your Dolfi


      How to position the clothes and the device 

      The device needs to be placed in water in the center with the logo facing upwards. Let’s get one thing straight - your Dolfi is not meant for large washing loads but should instead be used for small loads and particularly delicate clothes. Ensure that the clothes are not packed too tightly. If there’s not enough water for the clothes to float freely, you’ll have less than ideal cleaning results. 

      Take note that you need about 5 cm of only water (no clothes or other objects) directly above the device. Your clothes should be placed in such a way that there’s an opening in the middle with the device being visible when looking into the container. This ensures that the ultrasonic energy can be radiated in the water to create the optimal conditions for cleaning. 

      An exception is when you’re washing only 1 item with a heavier stain. You’ll then need to place stained area directly above the device, while maintaining the 5 cm gap of only water. That’s where the energy radiation field is the strongest. 

      Dolfi and stains 

      If you have some stains on your clothes, you would generally try to pre-treat the stains before throwing them into a conventional washing machine. The same is true for Dolfi – you need to give special treatment to certain stains before the normal washing cycle. You can make use of a detergent enhancer or stain removing solution

      However, you’ll be happy to hear that Dolfi is great at removing common stains such as red wine, cacao, coffee, many juices, blood, sweat, and oil.

      Some stains that have large particle sizes, such as ketchup or mustard, will require an initial treatment or rinse in order to remove the heavy bulk of dirt. For those ‘eviler’ stains - detergent enhancer or stain remover will help you achieve the best results. 

      When you’re washing your swimwear, you don’t need to use any detergent as Dolfi is able to clean the chlorine and sea salt effectively without it. 

      How do I know if it’s working? 

      Due to the nature of ultrasound, which is beyond the capabilities of human hearing, it’s quite difficult to see or hear whether or not your clothes are really being cleaned. That’s because the device is completely inaudible to the human ear but take a quick video with your phone and the microphone will pick up a sound that’s so powerfully loud, you’ll barely need any other reassurance. 

      Another way you can test the functionality of the device is to simply put your Dolfi in a transparent container with enough water, (logo facing up), put a source of light next to the water (like your phone’s flashlight), switch on the device and then you’ll see millions of beautiful little bubbles moving around due to the ultrasonic waves doing its thing. And there you go! 

      We’ll be providing more educational pieces on different things you can wash with your small, but oh-so-powerful Dolfi. If you ever feel lost the How to use Dolfi - AKA The Holy Grail should be your go-to. Stay tuned and learn more on how to stay fresh with Dolfi. Anywhere you go.