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Every starter kit includes the BKT TD-4279 meter, a lancing device, lancets, test strips (glucose, ketone, or both depending on your kit), a carrying case, batteries, and a quick-start guide. Everything you need to start testing right out of the box.

Yes. The BKT TD-4279 is FDA-cleared for over-the-counter blood glucose and ketone testing. No prescription required.

Intended Use: This Best Ketone Test Ketone and Glucose Meter is intended for the quantitative measurement of glucose in fresh capillary whole blood from the finger, and for the quantitative measurement of β-Ketone (beta-hydroxybutyrate) in fresh capillary whole blood from the finger. The system is intended for in vitro diagnostic use and for single-patient use as an aid to monitoring the effectiveness of a diabetes control program. The system should not be used for the diagnosis of, or screening for, diabetes, nor for use on neonates.

No, only BKT TD-4279 glucose and ketone test strips.

These are compatible test strips for both the original Keto-Mojo TD-4279 meter and the BKT TD-4279 meter. Make sure your meter matches the image below.

Every new box of ketone test strips includes a small ketone code strip — also called a code chip — that programs your meter to read that specific batch accurately. You'll need to code your meter every time you open a new box.

Where to find it

The code strip (code chip) is inside the ketone strip box, between the strip vial and the instruction sheet.

How to code your meter

1. With the meter off, insert the code strip (code chip).
2. Wait for the code number to appear on the display.
3. Check that the code on the display matches the code printed on your strip vial — they should be identical.
4. Remove the code strip. The meter will display “OK” — your meter is now coded for this box.

You only need to do this once per box. Every strip from that box will use the same code.

If the codes don't match

Stop and repeat the coding steps above. Testing with a mismatched code will give you inaccurate readings. If the codes still don't match after a second try, the code strip (code chip) may be expired or damaged — contact us at care@bestketonetest.com with your order number and we'll send a replacement.

Do I need to code my meter for glucose strips?

No. Coding only applies to ketone strips. Glucose strips don't require a code strip or code chip.

BKT blood ketone strips measure beta-hydroxybutyrate (BHB) directly in your blood, which is the most accurate and reliable way to track ketosis. Urine strips measure acetoacetate, a byproduct that becomes less detectable as your body adapts to ketosis — so they get less useful over time. Breath analyzers measure acetone and can vary with hydration and breathing patterns. For precise ketone levels, blood testing with BKT strips is the gold standard.

No. Each BKT test strip is single-use and should be discarded after testing.

Store in a cool, dry place. Keep strips in the original vial with the cap tightly closed. Do not use strips past the expiration date printed on the vial.

Each BKT test strip requires just 1.0 µL — a tiny drop from a quick fingertip prick.

First, take a breath — this is one of the most common things people reach out about, and in the vast majority of cases it comes down to one of a few simple, fixable things rather than a faulty meter. Run through this list and you'll usually spot it.

Quick things to check

• Ketone strips that aren't coded. Every new box of ketone strips needs its code strip, and a mismatched code will throw off ketone results. See how to code your meter →
• Low battery. A meter can still power on with a weak battery yet give off readings. Swap in two fresh AAA alkaline batteries and test again.
• Expired or mis-stored strips. Check the expiry date on the vial, and make sure strips have been kept in their original vial with the cap closed, away from heat, moisture, and sunlight.
• A used or damaged strip. Strips are single-use. Re-inserting one, or using one that's been handled a lot, can skew the result — always start with a fresh strip.
• Not enough blood. If the strip doesn't fully fill, the reading can come back low or error out. Warm your hands, let them hang down for a few seconds, and massage your finger pad to get the blood flowing. Then use a fresh strip and apply a full drop as soon as it's ready.
• Temperature. Testing outside the 50–104°F (10–40°C) range affects results. Let the meter and strips come to room temperature first.
• Hands and technique. Wash and fully dry your hands before testing — food, sugar, lotion, or water on the fingertip can contaminate the sample.
• Comparing to a lab or another meter. Home meters read a small drop of capillary blood from your fingertip, which naturally differs a bit from a lab's venous draw or a different brand. Small differences are normal, not a malfunction.

Still seeing numbers that don't add up after checking these? Please don't second-guess it on your own — reach out right away and a real person will get to the bottom of it with you and make it right.

The BKT TD-4279 exceeds strict FDA accuracy standards: ±15 mg/dL for glucose readings at or below 100 mg/dL, and ±15% for readings above 100 mg/dL. Ketone precision is CV < 7.5% for readings above 1 mmol/L.

With the BKT TD-4279, glucose results appear in 5 seconds and ketone results in 10 seconds. Both require just 1.0 µL of blood — a tiny drop from a quick fingertip prick.

The included lancing device has adjustable depth settings so you can find the most comfortable level for your skin. Most users describe it as a quick, mild pinch that's over in a second.

Good news — your meter is easy to look after, and a little care goes a long way. The simplest habit of all: wash and dry your hands before and after testing. That keeps dirt, dust, and germs away from both the meter and your strips, and it's most of the job done.

A quick wipe-down

Give the meter a gentle wipe whenever you notice anything on it, and a more thorough clean about once a week. There are two small steps:

1. Clean first. Use a disinfecting wipe to remove any visible dirt or spots from the outside of the meter.
2. Then disinfect. Use a fresh wipe to go over those same surfaces once more. The first wipe cleans, the second protects.

Please skip harsh chemicals and solvents — a standard disinfecting wipe or towelette is all you need, and anything stronger can damage the meter.

If someone helps you test

If a family member or caregiver handles the meter for you, a quick clean and disinfect of the meter and lancing device beforehand keeps everyone safe.

One important note on the lancing device

The lancing device and lancets are for one person only — never shared, even with people you're close to. Sharing them can pass on infection, so each person should always have their own.

That's really all there is to it. If you're ever unsure about anything, we're glad to help — just reach out.

Yes. All BKT starter kits ship free within the U.S. We also ship to Canada and internationally.

Yes. BKT products are also available on Amazon U.S. for your convenience. You can find our full range of starter kits and test strips there.

Yes. BKT meter kits and glucose test strips are FSA/HSA eligible, so you can use your pre-tax health savings to purchase. Ketone test strips may also be eligible depending on your specific plan — check with your FSA/HSA provider for details.

BKT glucose test strips are FSA/HSA eligible. BKT ketone test strips may also be eligible depending on your plan — check with your FSA/HSA provider.

Yes. The BKT TD-4279 connects via Bluetooth to the BKT Health app, available on the Apple App Store and Google Play Store. Use it to log readings and track your progress over time.

The BKT TD-4279 stores up to 1,000 readings with date, time, and testing mode. You can also review day averages across 7 to 90-day windows, broken out by before-meal, after-meal, and general readings.

E-b appears when the battery is too low to perform a test. Replace both AAA alkaline batteries immediately.

E-2 appears when the test strip or code chip is expired. Check the expiry date of the strip and repeat with a new lot if necessary. Also verify the date set on your meter is correct.

E-U appears when a used test strip is inserted. Discard it and repeat with a new test strip.

E-t appears when ambient temperature is above or below the system operation range of 10°C to 40°C (50°F to 104°F). Move to a room-temperature environment and repeat the test after the meter and strips are within range.

E-F appears when the test strip is removed while counting down, or when there is insufficient blood volume. Review the instructions and repeat the test with a new strip.

These codes indicate a problem with the meter. Repeat the test with a new test strip. If the meter still does not work, contact BKT Customer Support at care@bestketonetest.com.