Tempdrop vs. Natural Cycles: Which Is Better for Cycle Tracking?

By Emily Shaw

Edited by Korana Braun

Fact-check by Gemma Rigby

Updated February 12, 2026

There are many cycle tracking devices out there to choose from, making it challenging to know which one to invest in, and, more importantly, rely on to help you achieve your goals of trying to conceive or track your cycle.

Femtech has come a long way over the years. While general wearables like the Apple Watch or Oura Ring are great for health, practicing fertility awareness requires precision. To accurately track your cycle and know which days you're the most fertile, you need a specific basal body temperature device.

Your fertile window is usually a few days before or during ovulation and can be unpredictable. This study showed that 68.2% of women believed they had timed intercourse mainly within the fertile window of the menstrual cycle in their attempts at conception, but only 12.7% could accurately identify this window.

It's important you find the best fertility tracker to suit your needs. Utilize this guide to compare the pros and cons of using Tempdrop vs. Natural Cycles and decide which is best for you.

» Struggling with fertility tracking? Follow these 5 simple steps to get started

Tempdrop vs. Natural Cycles at a Glance

Features	Tempdrop	Natural Cycles Oral BBT Thermometer
FSA/HSA Eligible	Yes	Yes
User Experience	- Convenient - Easy-to-navigate app - BBT measured automatically	- Easy-to-navigate app - BBT measured orally - Oral temps are easily influenced by time changes/disturbances
Main Features	- Tracks fertile and non-fertile days for conception - Accurately measures BBT - Tracks sleep quality - Filters out disturbances in daily temps - Learns unique cycle patterns for accurate results - Tracks PMS pain, sex drive, mood changes - Premium includes cervical mucus interpretation, temperature data interpretation, ovulation day indication, fertility window insights	- Tracks fertile and non-fertile days - Stores entered BBT data - Learns unique cycle patterns - Tracks PMS pain, sex drive, mood changes
Best for	Women who have irregular schedules, middle-of-the-night wakings, or who want to track their sleep quality	Women who prefer oral temperature tracking
Price	One-time purchase: $189*	Annual membership: $149.99*

*Including Tempdrop's wearable sensor and two months free premium charting app. After that, the premium subscription is available at $6 usd/mo or $48 usd/year.

*Including NC BBT oral thermometer. The oral thermometer is $14.50 as a stand-alone product.

Tempdrop is an FDA-registered, wearable monitor and app that tracks your core body temperatures while you sleep via a comfortable and adjustable armband. Natural Cycles is an FDA-cleared app with an accompanying basal body oral thermometer that also uses your temperatures to help you track your cycles and is often marketed as digital birth control.

Temdrop and Natural Cycles are both FSA/HSA eligible. Tempdrop measures your basal body temperature while you sleep and tracks your sleep quality, while with the Natural Cycles app, you have to measure your BBT orally and enter data in the app.

» Here's how to have Tempdrop covered by HSA or FSA

a woman sitting on a couch next to a phone

Tempdrop Fertility Tracker

What is Tempdrop?

Tempdrop is a smart wearable thermometer and charting app combo that helps you easily and conveniently track and monitor your fertility window. The sensor is worn on the upper arm during sleep to accurately measure your basal body temperature (BBT). It also enables you to track additional fertility data to help you identify your fertile window, in real time.

The Tempdrop Fertility Tracker uses AI technology and a patented algorithm to learn your temperature patterns on a nightly and monthly basis by measuring your basal body temperature (BBT) while you sleep. It syncs this data to your phone to help you track your fertility each day and each cycle to help you conceive. You have the option to choose from two paths:

Get Pregnant
Cycle Tracking

In addition to these two paths, there's also the added features of Irregular Cycles (automatically detected after two cycles) or Pregnancy Mode.

Wearable fertility monitors help you confirm when ovulation has occurred by identifying the temperature rise (or spike) that's a result of an egg being released and your body secreting the hormone progesterone.

"As a mother of young children who often wake me up at night, I have found Tempdrop to be the perfect solution for tracking my cycles. The traditional BBT thermometers are just not feasible, and I rely heavily on Tempdrop's ease and convenience."

In terms of the added app features, it doesn't get better than the Tempdrop Academy and the built-in community feature, which are helpful when learning about your cycle and fertility tracking.

Pros

Ease of use and comfort
Tracks irregular periods and sleep cycles
Works while you sleep (no need to wake up at the same time each morning)
Sensor syncs with the app
Accurately identifies the fertile window and peak day (Validated by this 2025 study)
Filters out disturbances based on your unique nightly and monthly temperature patterns
Integrates with Read Your Body, Apple Health, Google Health, ChartNeo, Kegg, and Ovuview apps

Cons

You have to remember to turn it on (though it stores data even if you don't sync immediately)
Not approved for contraceptive use

Natural Cycles App

What is Natural Cycles?

Natural Cycles is an app that uses an algorithm to track your fertility based on basal body temperature. You can track your fertility status by measuring your temperature with a basal body thermometer, entering it into the app, and letting the algorithm handle the rest.

Natural Cycles is an FDA-approved app + thermometer that analyses your basal temperature readings and your menstrual cycle information to let you know when you're fertile or less likely to be fertile (often called safe days). There are three plans to choose from:

Birth Control
Plan Pregnancy
Follow Pregnancy

You need to download the app, select your plan, input your menstrual cycle information, and enter your temperature (typically measured orally after you wake up). The app algorithm will learn the pattern of your cycle to work out your fertility status.

Pros

Some users prefer oral temperature tracking
Helps you identify fertile window
FDA approved as a method of birth control

Cons

Many women find they need to temp at a similar time each morning to get accurate data
Does not filter out the outlier temperatures (like alcohol or illness) effectively
Fixed cover line that does not adjust based on current cycle data

Tempdrop vs. Natural Cycles: Efficacy and Algorithm

The efficacy of the symptothermal method is evidence-based. Research shows it to be up to 99.6% effective with perfect use, and 98.2% effective with typical use. Tempdrop takes thousands of measurements during your sleep and analyzes the cycle data with its algorithm to get an accurate BBT reading and can be used in conjunction with fertility awareness methods.

A recent study validated Tempdrop's accuracy against clinical urine LH tests (like Clearblue). Analyzing over 190 cycles, researchers found Tempdrop had 98.6% accuracy in detecting the fertile window. Researchers concluded that the wearable is an "effective alternative to urine ovulation tests" for determining the timing of ovulation.

This study also highlights a critical advantage of measuring at the upper arm rather than the wrist. While wrist-based wearables (like Ava) generally achieve around 93% accuracy, Tempdrop's axillary position achieves 98.6%. That gap might look small, but it actually represents an 80% reduction in error. By moving the sensor from the exposed wrist to the protected underarm, you eliminate four-fifths of the potential error, taking you from having a "general idea" of your cycle to having clinical-grade confirmation.

The Natural Cycles algorithm informs you whether and when you can become pregnant based on the information that you enter into the application. Efficacy is also informed by user consistency. For most women, this comes down to how convenient the product is to use and how well it interprets your data.

Products that are more manual and have stricter rules of use (like oral basal body thermometers) can often become less effective for the average user if they are sensitive to disturbances or have an irregular sleep schedule.

Winner: Tempdrop

Tempdrop vs. Natural Cycles: User Experience

From a user perspective, both apps are easy to navigate. However, you’re using a device every single day, so comfort matters.

How does Tempdrop work?

With Tempdrop, you just need to make sure the sensor is turned on and placed correctly on your arm before sleep. Simply place the sensor over the axillary artery area below the armpit. To find the correct position, flex your arm and find the soft area between the bicep and triceps. (Curvier women may need to wear Tempdrop closer to their armpit over the thinnest skin). Take the Tempdrop off in the morning and sync it with your smartphone to download the temperature data you need.

With Natural Cycles, you can manually record your daily basal body temperature (BBT) or sync via Bluetooth. Then, you need to wait for the algorithm to determine your fertility. This can often lead to missed days and missed data, especially if you forget to reach for your thermometer before sitting up.

Winner: Tempdrop

Tempdrop vs. Natural Cycles: Main Features

Thanks to Tempdrop's ease of use and AI technology, you can trust that it will analyze your data accurately. The app filters out the outlier temps that can happen from stress, disturbed sleep, or a glass of wine before bed, so you can avoid any confusion on whether or not you have ovulated. No matter what happens in your life, Temdrop's patented algorithm learns your unique temperature patterns.

Plus, Tempdrop's premium option includes:

Cervical mucus interpretation (mucus categories)
Temperature data interpretation
Ovulation day indication
Fertility window insights

You can also add LH (Luteinizing Hormone) tests, PMS symptoms, and personalized notes to the app for reference.

Natural Cycles' main feature is storing your last temperature, so if you do forget to enter it in the app when you wake up, you can catch up later on. There is also space for you to add information about any PMS, pain, sex drive, or mood changes and a graph feature you can use to see patterns.

Winner: Tempdrop

Tempdrop vs. Natural Cycles: Price

The Tempdrop's full price is $189, but there can be promotions that bring the cost lower. You can use the app for free or upgrade to the premium version for $6/mo or $48/year. Tempdrop also has a 12-month refund* and extended warranty*. Each Tempdrop purchase comes with a 2-month free trial of the premium app subscription.

The Natural Cycles thermometer is $14.50 as a stand-alone product. To use their app and algorithm, however, you would need to invest in the Natural Cycles annual membership of $149.99, which includes the cost of the thermometer.

*Optional upgrade

Both are FSA/HSA eligible.

Winner: Tempdrop

Final Thoughts

As you can see, Tempdrop vs. Natural Cycles results in a clear winner for a multitude of reasons.

Whether you want to conceive or simply want to know your body better, Tempdrop makes the fertility charting process seamless.

If you are someone with irregular periods, struggle with sleep disturbance, have failed at oral temping in the past, or want to integrate with other charting apps, it's worth giving Tempdrop a try!