Measuring your ketone levels is the secret to long-term ketogenic diet success. 

But choosing between a Ketone Breath Meter vs Urine Strips isn’t that simple.

Both tools are popular among ketoers, but they differ in accuracy, convenience, and user experience.

Here’s everything you need to know.

• Testing Method
• Accuracy
• Convenience
• Invasiveness
• Learning Curve
• Cost
• Calibration
• Influencing Factors
• Best for

Ketone Breath Meter vs. Urine Strips

The primary difference between a ketone breath meter vs. urine strips is that a breath meter measures current acetone levels in the breath, while urine strips indicate past ketone bodies in the urine, as urine can stay in the bladder for hours before excretion.

Method of Testing

Breath Meter: Breath acetone meter measures acetone levels in the breath. Acetone is the third and least abundant ketone body. The testing process involves breathing into the device, and the device provides the level of acetone in parts per million (PPM). This method is non-invasive and can be done at any time. (1)

Urine Strips: Urine strips detect ketone bodies, primarily acetoacetate, in the urine. Testing with urine strips involves peeing on a special strip and waiting for it to change color. The color indicates the level of ketones in your body. This method can be a bit messy and may not always be convenient.

A ketone breath meter is easier to use than urine strips. It’s quick, easy, and can be done anywhere. Urine strips are a great option if it’s your first time on the ketogenic diet and you don’t mind a little extra work, urine strips could be a good choice because they’re usually cheaper. 

Accuracy

Breath Meter: A ketone breath meter is an accurate way of measuring ketone levels because it measures the current state of acetone in your breath. Breath monitors use sensors that are very sensitive to acetone and provide a specific level of acetone. (2)

Urine Strips: Urine strips are not an accurate way of measuring ketone levels because it’s not a real-time measurement of ketone levels. Urine strips reflect past ketone levels since urine can remain in the bladder for hours before being excreted. (3)

A ketone breath meter is more accurate than urine strips. It’s more reliable and provides real-time, consistent results. The urine strips can vary and may not represent your current ketone level accurately. 

Convenience

Breath Meter: Using a ketone breath meter is convenient because you just breathe into the device, and it provides a measurement. Typically, in less than a minute. It’s perfect for use on the go. Plus, it’s reusable, so you can test your ketone levels as often as you want without needing to buy more supplies. 

Urine Strips: Urine strips are less convenient to use because you need to pee on the strip, which is not always convenient. Especially when you are on the go. Peeing on a urine strip may also have a “yuck factor” for some users. Plus, you have to buy new strips every time you want to test.

A ketone breath meter is more convenient to use than urine strips. It’s faster, and you don’t need to keep buying supplies. It doesn’t have a “yuck factor,” and you can easily take measurements on the go. This is a big plus if you are on a ketogenic diet.

Cost

Breath Meter: The average price of a ketone breath meter is between $50 and $300, depending on the sensor and brand. For higher-end devices, there’s also the cost of calibration, around $30 to $70 per year. This ensures high accuracy.

Urine Strips: The average price of a pack of urine strips is between $10 to $20. But these are single-use. You use them once and throw them away. If you test ketones often, you’ll have to keep buying more. Over time, this can add up.

Ketone breath meters have a higher upfront cost than urine strips but are cheaper in the long run. It makes sense for users who want accuracy and to measure ketone levels several times a day. Urine strips are great for beginners who want a generic verification of their state of ketosis.

Calibration

Breath Meter: Most ketone breath meters need regular calibration in order to provide accurate measurements consistently. The average calibration interval is around 1-2 times per year, depending on the number of test cycles. Most high-quality brands offer calibration services. (4)

Urine Strips: Urine strips do not require calibration. Each strip is single-use, and its reactivity is predetermined during manufacturing. There’s no mechanism to adjust or calibrate the strip’s sensitivity or reactivity. But urine strips have about 6 months shelf life after the bottle has been opened. (5)

Ketone breath meters require regular calibration, while urine strips do not. Calibration ensures the accuracy of measurements and is best for keto dieters who want to measure ketone levels several times per day. Urine strips become less accurate once the body becomes more keto-adapted.

Influencing Factors

Breath Meter: Ketone breath meter results are influenced by breathing technique and outside factors. The main influencing factors include the time of the measurement, fasting, exercise, alcohol, foods and drinks, and even smoking.

Urine Strips: Urine strips results are influenced by dehydration, certain medications, and how long the user has been on the ketogenic diet. Urine strips become less accurate once the body adapts to ketosis and excretes fewer ketones in urine.

Both ketone breath meter and urine strip measurements are influenced by outside factors. Breath meter results are affected by certain lifestyle factors, which can be avoided. Urine strips are less influenced by lifestyle factors, but their accuracy decreases over time. 

Invasiveness

Breath Meter: Using a ketone breath meter is a non-invasive way to measure ketone levels. It’s a non-invasive method as it only requires breath and doesn’t involve any bodily fluids or penetration of the skin. 

Urine Strips: Using urine strips is a non-invasive way to measure ketone levels. The user must urinate either directly onto the strip or into a container, after which the strip is dipped into the sample. While this method doesn’t involve breaking the skin, some users might find the process a bit personal and potentially messy.

Breath ketone meters are generally considered less invasive than urine strips because they only require a breath sample. Urine strips, although not invasive in the traditional sense, require a more personal sample collection, which some might find less comfortable or convenient.

Learning Curve

Breath Meter: For consistently accurate results, the learning curve of ketone breath meters is high. To achieve high accuracy, the user needs to use the correct breathing technique, take measurements between meals and exercise, and avoid influencing factors like alcohol and minty products.

Urine Strips: The learning curve of using urine strips is very low. The user simply collects a urine sample and dips the strip, waiting for a color change. The resulting color is then compared to a reference chart to determine ketone levels. While there’s a need to understand the color gradations, the overall process is straightforward.

Breath ketone meters have a higher learning curve than urine strips. This is because breath monitor readings are strongly affected by user lifestyle factors like food and exercise. While urine strips are easy to use and don’t have any technical procedures.

Best For

Breath Meter: A ketone breath meter is best for people who are serious about their ketogenic diet and want to know how deep in ketosis they are. It’s ideal for users who want to measure ketone levels several times per day and need fast results.

Urine Strips: Urine strips are best for people who are first time trying the ketogenic diet and just want to know if they are in ketosis or not. They are less accurate once the body is adapted to ketosis, but they are cheap and easy to use.

Both ketone breath meters and urine strips are popular among those on a ketogenic diet. However, many on a long-term ketogenic diet prefer breath meters for their convenience and consistent accuracy.