The Best Basal Thermometers to Help You Kick-Start Your Family Planning Journey

The Easy@Home Smart Basal Thermometer is an all-in-one device that tops our list

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When you’re ready to start your journey to conception, nailing down your ideal ovulation window can be a critical step. While there are a host of ways to demystify timing, like using ovulation strips, phone apps, and tracking your period, a basal thermometer is a tool that can help you get one step closer to conceiving.

Reviewed & Approved

The Easy@Home Smart Basal Thermometer is a beginner-friendly option that seamlessly syncs with an app to make results easier to interpret. The Ava Fertility Tracker consistently monitors your vitals to provide you with a real-time picture of your fertility.

“In most women, the body's normal temperature will increase slightly during ovulation, 0.5 to 1 degree Fahrenheit, and remain high until the end of the menstrual cycle,” Nicole A. Sparks, MD, an Atlanta-based obstetrician-gynecologist, tells Verywell Family. The rise in basal body temperature (BBT)—the term simply refers to your body’s temperature at rest—will happen at the same time as ovulation, so tracking it every morning it is a good method to use to help establish your window of fertility. (But be aware that you may be fertile just before ovulation as well.)

Basal thermometers are able to read 1/10 or 1/100 of a degree, picking up the slight rise and fall that regular thermometers can't show. When it comes to choosing a basal thermometer, you also want to find one that is easy to use, suits your needs, and fits your budget.

We’ve rounded up the best basal thermometers to help you with your natural family planning journey.

Best Overall: Easy@Home Smart Basal Thermometer

Easy@Home Smart Basal Thermometer

Easy@Home

Pros
  • Automatically syncs with the app

  • Reads 1/100 of a degree

  • Backlit screen

Cons
  • Long result time

  • Loud beeping

With Bluetooth capability that makes loading daily results into an organized chart, the Easy@Home Smart Basal Thermometer is our best overall pick because it is beginner-friendly and works in conjunction with other fertility tracking products. The super-precise thermometer can read to 1/100 of a degree, picking up on the slight changes in your temperature.

 If you are new to charting, temping, and tracking your cycles, the Premom app will seamlessly sync, log, and organize your results, making interpretation clearer. You can store up to 30 results on the thermometer and unlimited results on the app, so you can skip writing down your temperature every day. However, if you do like to take notes instead of relying on the app, the backlit display includes your temperature, the date, and the time. It takes 90 to 120 seconds to get results, which can definitely be cumbersome in the morning.

Display: Digital | Response time: 90 to 120 seconds | Battery type: Lithium metal battery included

Best for Beginners: Natural Cycles Plan a Pregnancy Kit

Natural Cycles Plan a Pregnancy Kit

Natural Cycles

Pros
  • Includes ovulation strips and pregnancy tests

  • App is FDA cleared

Cons
  • Must pay for app subscription after six months

  • Have to add results to app manually

If you are new to fertility tracking, understanding the results can be a stress-inducing experience. The Natural Cycles Plan a Pregnancy Kit comes with the basal thermometer, a six-month app subscription, 10 ovulation strip tests, and five pregnancy test strips—which is everything you need to get started learning about your cycle. The FDA-cleared app uses a complex algorithm to identify ovulation patterns so that you can plan effectively.

The basal thermometer is easy to use and stores one previous reading, in case you forget to write it down. The simple, straightforward approach is a non-intimidating way to ease into fertility tracking.

Display: Digital | Response time: Not listed | Battery type: Not listed

Best Wearable: Ava Fertility Tracker

Ava Fertility Tracker

Ava

Pros
  • Real-time tracking

  • Bracelet is FDA cleared

  • Convenient technology

Cons
  • Expensive

Smart, wearable, and convenient; the Ava Fertility Tracker approaches conception planning from a unique perspective. The Ava tracker sets itself apart as a wearable device that continuously monitors your temperature at your wrist. This provides both real-time results and a more complete look at your body’s temperature changes, which could help you determine when you might be more likely to conceive. Additionally, the bracelet is the only FDA-cleared wearable basal thermometer. 

To use the Ava tracker, simply wear it at night, and when you wake up in the morning, sync it to the app, which will do all your calculations for you. While you are snoozing, the Ava technology is collecting data every 25 seconds to help you narrow down your fertility window. From your temperature and pulse rate to your heart rate variability and sleeping patterns, the bracelet is consistently checking various physiological parameters that impact your fertility (that would be a headache to track on your own).  While the price point is higher than other options, it is FSA and HSA eligible. 

Display: No display, only app | Response time: Not listed | Battery type: Rechargeable

Best Smart Thermometer: femometer Digital Basal Thermometer

femometer Digital Basal Thermometer
Courtesy of Amazon.
Pros
  • Button-free

  • Fast response time

  • Measures up to 1/100 of a degree

Cons
  • $10 monthly subscription

The most important step in basal body temperature tracking is jotting down your results to help establish patterns in temperature changes. The Fermometer Digital thermometer makes that process easier thanks to its Bluetooth capability. Once you take your temperature, the results are automatically transmitted to the app, which translates the information into a clear line chart.

The digital, backlit thermometer is free of buttons and switches, so all you have to do is pop it in your mouth, and within 30 seconds, you’ll have a precise result. Made to be discreet, the Fermometer’s beeping sound can be adjusted to suit your needs. We think the app makes interpreting results much easier, however, it does require a $10 monthly subscription to use. 

Display: No display, only app | Response time: 30 seconds | Battery type: CR123A battery included

Best Budget: iProven Digital Basal Thermometer

iProven Digital Basal Thermometer

iProven

Pros
  • Free subscription

  • Budget-friendly

Cons
  • Not backlit

Sometimes basic is best, and the iProven Digital Basal Thermometer is an uncomplicated option that gets the job done. Operating like a regular thermometer, the iProven sits under your tongue and delivers a result within 60 seconds. With the ability to detect a temperature to 1/100 of a degree, the iProven thermometer will pick up the important slight changes.

We appreciate that the app doesn’t require a paid subscription, and while it doesn’t automatically sync, it gives you a safe place to jot down your results and read them throughout the month.

Display: Digital | Response time: 60 seconds | Battery type: LR41 battery

Best Kit: Easy@Home Ovulation Kit

Easy@Home Ovulation Kit

Easy@Home

Pros
  • Includes ovulation strips

  • Free subscription to app

Cons
  • Manual entry of results

For seasoned fertility trackers, this Easy@Home Ovulation Kit is a dream. Deciphering the best time to try to conceive can be a multifaceted journey, and this kit has you covered from all angles. Along with the thermometer, you can use the 50 ovulation strips tests to capture your luteinizing hormone (LH) surge. Then you’ve got 20 pregnancy tests to see the results of your efforts.

The sensitive basal thermometer is able to detect 1/100 of a degree to offer a precise and accurate measurement. We love that you can add all of your results to the free app, which then can translate them into charts and graphs for easier interpretation.

Display: Digital | Response time: Not listed | Battery type: Not listed

The Easy@Home Smart Basal Thermometer is a seamless option that is great for people new to tracking as well as those who are more experienced. We also recommend the Ava Fertility Bracelet for a full picture view of fertility that goes beyond your basal temperature.

How We Selected

We researched several basal thermometers, considering their accuracy, precision, price point, and ease of use to determine the best options on the market. We also consulted with OB-GYN Nicole A. Sparks, MD, to better understand what to look for when buying a basal thermometer.

What to Look for in a Basal Thermometer

Ease of Use

To track your basal body temperature accurately, you have to use the thermometer every morning as soon as you wake up. For a product that requires that much use, you’ll want it to be as easy as possible to figure out. Some thermometers are more straightforward than others, and depending on your lifestyle, you may fare better with a set-it-and-forget-it style wearable tracker. 

Budget

It is no secret that fertility and reproductive health management can be an expensive undertaking. Thankfully, quality basal thermometers are available at various price points. You can choose the features that fit within your budget and lifestyle without compromising on effectiveness. 

Basal vs. Traditional Thermometers

“A basal thermometer and regular thermometer are very similar, but the biggest difference between a basal thermometer and a regular digital thermometer is that a basal thermometer will measure in very small increments sometimes to 1/10 of a degree,” Dr. Sparks says. Since the rise and fall of your temperature is so slight, a regular digital thermometer simply won’t be able to capture it.

Frequently Asked Questions

  • What is a basal body temperature?

    A basal body temperature is your body’s temperature at rest. “Your body temperature changes slightly during your menstrual cycle. Your body temperature is slightly lower in the beginning of the cycle and rises when you ovulate,” explains Dr. Sparks. The best way to capture this temperature is while you are still lying in your bed after a full night of uninterrupted sleep. 

    “Basal thermometers are not 100% accurate, so you don't want this as the primary way you track ovulation,” she adds. “Many factors such as fever, sickness, stress, alcohol, or even interrupted sleep and travel zone time differences can affect the accuracy."

  • What should my basal body temperature be?

    While there isn’t a hard and fast rule when it comes to nailing down an exact number for your BBT, there is a range of changes that you can keep an eye out for. “In a normal menstrual cycle, the basal body temperature begins to rise one or two days after the luteinizing hormone surge,” Dr. Sparks explains. That’s the hormonal signal for the body to release an egg from the ovary. 

  • Where do I put a basal thermometer?

    Unless it is a wearable device, a basal thermometer should be used orally and placed under your tongue. While the sensitivity of a basal thermometer differs from a traditional oral thermometer, you use them the same way.

Why Trust Verywell Family

Latifah Miles is a commerce editor at Verywell Family and has several years of experience shopping for the best products for parents and caregivers and their families. She thoroughly researches and analyzes products to find the best options on the market.

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