Best refractometer


To get consistently accurate readings from an analog refractometer, you must thoroughly clean it after every use. Otherwise, the tool may develop an erroneous or fuzzy dividing line.

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Which refractometers are best?

If you would like to try home brewing, you need a refractometer. A refractometer allows you to measure sugar concentration in the wort. You then use this measurement to calculate the beer’s alcohol content. A refractometer is also useful when making wine, fruit juice, honey and more.

The best models are accurate and easy to use. The Milwaukee Digital Brix Refractometer, for example, is a high-end digital model that gives you accurate results in seconds. It is also versatile enough to be used in a wide variety of food applications, ranging from making maple syrup to making wine.

What to know before you buy a refractometer

What is a refractometer?

A refractometer is a device used to measure the concentration of a particular substance in a solution. The device does this not by measuring the substance but by measuring the degree to which light is bent while traveling through the solution. This bend is called the angle of refraction. Suppose you know what substance is in the solution, and you know the temperature of the solution. In that case, you can accurately calculate how much substance is present by measuring the angle of refraction. To facilitate calculation, refractometers have scales that are calibrated to give you a measurement at a glance.

What can you use a refractometer for?

A refractometer has a wide variety of practical uses. Brewers and winemakers can employ it to measure alcohol content. It can also be used by syrup and honey producers and individuals who make candy. A refractometer can help gardeners gauge photosynthesis by measuring the sugar, minerals, proteins and vitamins in a plant’s juices. The device can even measure the amount of nutrients in a glass of milk. In the automotive world, a refractometer can measure battery acid, diesel exhaust fluid, antifreeze and more. Or, you can use it to measure the salinity in an aquarium.

Refractometers can be analog or digital

There are two main types of refractometers: analog and digital. An analog model requires no power source (unless it is lighted) and offers the hobbyist an affordable yet accurate solution. Digital models cost significantly more but have bells and whistles, such as effortless calibration, and can obtain measurements at the press of a button. 

What to look for in a quality refractometer

Automatic temperature compensation

Refractometers are designed to work at specific temperatures. If you measure outside that temperature range, it is important to have a model with automatic temperature compensation. This is the best and easiest way to receive accurate readings.

Appropriate scale

A refractometer can be used to measure a wide variety of solutions. Each application requires a different scale. When purchasing a refractometer, make sure it has a scale that fits your needs.

Built-in LED

Depending on the environment, it can be frustrating to find a light source that allows you to read an analog refractometer easily. Some models feature built-in LEDs, so you can always see the results no matter how dim the ambient lighting is.


To function properly, you need to keep your refractometer clean and scratch-free. For this reason, it is wise to choose a model that comes with its own protective case.

How much you can expect to spend on a refractometer

Working within a tight budget, you can find an analog refractometer for less than $20. A digital model, however, will cost over $100. Most home users will likely find what they need near the lower end of the price scale.

Refractometer FAQ

Is it hard to use a refractometer?

A. It is very simple to get a reading on a refractometer. For analog models, place a few drops of the solution you measure on the unit’s prism, making sure it is evenly covered. Close the lid and hold the device up to a light source. Higher-end models may feature built-in lighting to make the reading easier to see, while digital models will simply display the readings in a matter of seconds. Even if you have never used a refractometer before, as long as it is calibrated properly, you can get accurate readings on your very first use. Depending on what you are measuring, you may need to do a math problem or two to get the information you require after noting the refractometer readings.

Is it hard to calibrate a refractometer?

A. The word “calibrate” may sound scary, but it’s really quite simple when it comes to a refractometer. Calibration for analog models is fundamentally the same—though you should always defer to the documentation that comes with your model. Place a drop or two of the test solution you will use to calibrate your refractometer on the prism. Hold the device up to the light and take a reading. If the reading is not what is expected, adjust the settings until you see the desired result. For a digital model, calibration often requires placing the solution on the device and pressing a button.

What are the best refractometers to buy?

Top refractometer

Milwaukee Digital Brix Refractometer

Milwaukee Digital Brix Refractometer

What you need to know: If you are looking for a refractometer that is easy to use and gives you precise measurements in seconds, this digital model is the one for you.

What you’ll love: Using just two or three drops of your solution, you can get results in about two seconds. Calibration is simple and the IP65 unit is dust-tight and water-resistant. The refractometer automatically shuts off after three minutes to save battery power.

What you should consider: This model is on the higher end of the price scale, but you are paying for convenience and ease of use.

Where to buy: Sold by Amazon

Top refractometer for the money

Aichose Brix Refractometer

Aichose Brix Refractometer

What you need to know: For individuals looking for an affordable refractometer for their home brewing needs, this model is a solid option.

What you’ll love: This unit is manufactured to test the sugar content and specific gravity of a liquid. It is suitable for home brewing, winemaking and gardening purposes as it provides readings of 0 to 32% Brix and 1.000 to 1.120 specific gravity. Purchase includes a handy storage case.

What you should consider: Calibration is extremely important in getting this unit to read accurately.

Where to buy: Sold by Amazon

Worth checking out

Aichose 4-in-1 DEF Antifreeze Coolant Refractometer

Aichose 4-in-1 DEF Antifreeze Coolant Refractometer

What you need to know: This four-in-one model is specifically designed for measuring automotive fluids.

What you’ll love: You can use this versatile refractometer to measure the freezing point of antifreeze, the specific gravity of battery acid, the effectiveness of windshield washer fluid and the urea concentration in diesel exhaust fluid. It features high-quality optics, smooth focusing and it’s designed to be corrosion resistant. 

What you should consider: Some users are not happy to discover that this model only measures Celsius.

Where to buy: Sold by Amazon


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Allen Foster writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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