keto mojo vs biosense comparison review
Home Metabolic Cancer Therapy Resources Keto Mojo v Biosense: Which is the Best Ketone Monitor?

Keto Mojo v Biosense: Which is the Best Ketone Monitor?

by Maggie Jones

I had a chance to do a head to head test of the Keto Mojo blood ketone meter and the Biosense breath ketone meter during my recent 8-day water fast.

I tested my blood and breath ketones using both multiple times throughout the day. My impression is below.

First, a quick reminder on why I planned to switch to Biosense:

  • Less cost: break even at 300 tests, $1.00 per test savings thereafter
  • Better accuracy: clinically proven precision vs “within 20%”
  • No finger pricking
  • Faster: I expected the time to blow and wait for results would be faster than pulling out my gear, pricking, taking a blood drop, and waiting for results
  • More convenient: Traveling with all my gear and storing extra strips isn’t a huge deal but I was excited to just slip the Biosense in my purse and be done with it.

Unfortunately, many of my expectations didn’t quite match reality after I was able to try the device.

Here’s how the Biosense compared to my Keto Mojo on factors of:

Or skip straight to the bottom line.

One quick note: The Biosense measures ketones using a unit called ACEs. 10 ACEs is roughly equivalent to 1.0 mmol/L of BHB blood ketones. 20 ACEs on Biosense roughly equals 2.0 on keto mojo, 30 ACEs approximates 3.0, etc. Just move the decimal point space to translate.

Finger Pricking: Advantage BioSense

The Biosense has the clear advantage here. For people like my sweet husband Brad who hate needles and blood, a breath meter really is the best solution, and Biosense is the only breath meter out there with clinically proven accuracy. In fact, I expect Brad to be the primary user of our Biosense.

However, if you’re tracking your GKI for therapeutic ketosis and not just your ketones, you’ll likely still need to prick for the glucose test. The alternative, which I’ve tried, is a continuous glucose monitor (CGM). A CGM only needs to be inserted every two weeks and will send 8 hours of recorded data to my phone via Bluetooth with just a tap.

Most of the time I’m not wearing a continuous glucose monitor, though – and most therapeutic keoters aren’t either. Instead, I’m using the Keto Mojo as my blood meter and can use the same drop of blood for measuring my ketones, too.

Biosense is therefore generally best in the finger-pricking department for those who are only tracking ketones and not GKI.

Cost: Advantage Biosense

Even though the up-front cost is substantially higher, there’s no incremental cost per test with the Biosense vs the average $1 per ketone test strip cost of the Keto Mojo.

If you plan to test more than 300 times, Biosense really does come out on top.

BiosenseKeto Mojo
Meter Cost$299$49 (comes with 10 strips)
Cost per ketone test (per strip)$0$1
Cost after 300 tests$299$339
Those monitoring their GKI will also need a monitor for blood glucose. Keto Mojo also acts as a blood glucose meter. Those are usually in the $30-40 range so I feel that $300 makes a good break even mark.

Time to Test: Advantage Keto Mojo

Ohmygod the Biosense takes so long to test. Over two minutes of noisy “preparing the device” before each test. Then usually 10 seconds to blow and sample, then 20 more seconds to analyze and display the results.

IF it doesn’t automatically start “deep clean” mode which takes well over 5 minutes. After my first day of testing I was in deep clean mode every time.

Note that, you only have a 2 minute 15 second window after “preparing the device” in which to test. If you get distracted and miss that window, you will need to wait over 2 minutes to prepare the device again. At my most focused, each test took 3 minutes.

Keto mojo takes 7 seconds to charge after insertion of a test strip. I usually prick during that time. Less than 5 seconds to register my blood drop and 10 seconds for results.

BiosenseKeto Mojo
Time to charge135 sec or 305 sec with deep clean8 sec
Time to sample9 sec4 sec
Time for analyze20 sec10 sec
Total test time164 – 334 sec22 sec
The biosense takes a long time to charge.
Biosense takes a while to charge and become ready for use – here it’s been over 4 minutes and we’re on cleaning cycle 2 out of 3.

Convenience: Debatable

The Biosense has less to keep track of, which is nice. Just the device itself in its small carrying case if I’m going out for the day. To conduct a test on the Keto Mojo I need the device, strips, and the lancet for pricking, all of which fit in the larger carrying case.

What I didn’t take into account with the Biosense was the fact that it needs to be charged so I need to keep track of it’s micro USB charger. It’s a little more brain space for my nomad life living out of a suitcase and adds the risk of running out of battery.

This could just be a problem with my limited mental bandwidth. The Keto Mojo requires keeping track of strips, the lancet, and backup lancet needles so pick your poison.

Really, it’s just the time investment and noise involved in Biosense testing that keeps me reaching for the Keto Mojo.

Size comparison of the keto mojo with strips and lancet (bottom) to Biosense.
Size comparison of the keto mojo with strips and lancet (bottom) to Biosense (top)

Accuracy: Debatable
Precision: Advantage Keto Mojo

Biosense actually paid for a clinical trial demonstrating its accuracy and I give them points for that. However, a deeper look at that research doesn’t show that it is necessarily more accurate than Keto Mojo. The results of their small trial (19 people) showed that Biosense results correlated strongly with blood meter results. That is to say, they were similar. Interestingly, breath ketone numbers seemed to lag behind blood numbers.

However, I have a real concern with my experience using the Biosense.

Biosense vs Keto Mojo: Precision and Repeatability

The biosense’s readings varied A LOT over the 3-5 minutes it takes to take a repeat reading. From 32 to 40 within 5 minutes and 39 to 25 within 3 minutes… keep in mind that these were all taken after 2 days of water fasting when multiple readings on my keto mojo were showing the same steady, repeated numbers when these readings were taken.

Biosense vs Keto: Mojo Accuracy

Legally, Keto Mojo readings are within 20% of your actual blood glucose. Frequently, Biosense readings differed from the Keto Mojo by more than 20%. Obviously, the truth could be somewhere in-between but it did raise some concerns on my part given that the Biosense differed from its own readings by more than 20% sometimes, as shown above.

Keto Mojo compared to Biosense shows more than 20% difference between readings.

Technology: Advantage Biosense

The Biosense comes with a nice app that makes pretty charts, which I like a lot. The device does become untethered from the app seemingly every test but it’s easy to re-tether and I’ve never lost data.

Biosense also integrates with Cronometer, the online tool most therapeutic ketoers use to track their eating and metrics. *

For the ketone mojo, I’ve been keeping track of my numbers in a Google spreadsheet and by manually entering into Cronometer.

* Note that, device data must sync to the Biosense app before it is imported to Cronometer – usually a half day delay or so.

Usefulness: Advantage Keto Mojo

I wasn’t sure what to call this section but the fact is that the Biosense isn’t that useful to me because it doesn’t measure ketones over 40 ACEs, the rough equivalent of 4.0 mmol/L BHB ketones.

Those using keto for medical, therapeutic reasons — especially those targeting GKI less than 1.0 — are usually over 4.0 ketones and need to know how much over to know if their GKI is less than one. The Biosense 40 limit tells you you’re under 1.0 GKI only if your blood sugar is under 72 mg/dL.

Honestly, I’ve maxed out the 8.0 limit on the keto mojo once before but going over 8 mmol/L of blood ketones is incredibly rare and not advised.

You can see how, for me, the straight line chart showing that my ketones measured as ACEs are over 40 is less helpful than knowing when they’re higher or lower in this range.

The Bottom Line: Keto Mojo vs Biosense

Biosense is best for:

  • People who are pursuing nutritional ketosis and don’t often need to measure ketones over 4.0.
  • People who hate the finger prick
  • People who plan to do at least 250 ketone tests and who value money more than time

If this is you, click here for $20 off Biosense! (note that the discount only displays during checkout.)

Keto Mojo is best for:

  • People pursuing therapeutic ketosis who spend much of their time in the 4.0+ ketone range.
  • Those tracking GKI without a CGM who have to prick anyway.
  • People who value time more than money and don’t mind the finger prick.

If this is you, click here for 15% off Keto Mojo

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Rob July 7, 2020 - 5:03 pm

Thanks for your blogs Maggie and glad you are doing well health-wise! Did you reach out to Biosense to see if you have a flawed device or is this standard isuses as far as you can tell? Regarding accuracy, app linking and time to startup and test?

Maggie Jones July 7, 2020 - 5:39 pm

Hi Rob! Great question!

I’ve heard they’re actively working on improvements and the device they sent me is a little older. I can’t vouch for the latest improvements, though, since I haven’t tried them. As far as accuracy, the Biosense does test for a different type of ketone. Blood tests test for BHB and breath meters for acetone so it’s possible I had higher BHB than acetone. I realized after I took some exogenous BHB ketones and it didn’t budge my Biosense readings.

To be honest, after about a month transition time I’ve gotten a lot more used to using the Biosense and tend to reach for it more often than my keto mojo these days. The noise doesn’t bother me as much and instead alerts me when it’s ready for testing so it doesn’t feel like it takes quite as long. I’ve heard from some other folks that the 2-5 minute prep time is pretty standard.

Thank you so much for the kind words, too!

Sharvo August 1, 2020 - 10:38 am

I am disturbed that all the cost comparisons that I see for Biosense infer that the device runs forever. I believe I heard their Product VP say in an interview that the cartridge is good for about two years. $300 every 2 years is not a savings.

Maggie Jones August 3, 2020 - 3:34 pm

Oh Sharvo! This is such great information. Thank you! I’d never heard that the Biosense only has a 2 year lifespan. I’ll check with the company but, in the meantime, it still makes sense for me to update the article to take this into account. Since I test multiple times per day and the biosense breaks even after 250 tests, it’s still a significant savings for me (two years would be over $1500 in test strips for me). Nevertheless, it’s a critical point for folks deciding. Thank you again!


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