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What is the best ovulation predictor kit?

If you’re trying to conceive an ovulation kit can help you pinpoint your fertile window. Knowing exactly when you ovulate in your cycle will greatly increase your chances of getting pregnant quickly.

An ovulation predictor kit or OPK can indicate precisely or give an estimation of a few days.

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Best Ovulation Tests for TTC | Get pregnant quickly when you use ovulation tests sticks. These bad boys help you pinpoint your most fertile days . Stork Mama

There are a few different types of OPKs on the market. Knowing the benefits of each type can help you to choose the one that is right for you.

We’ve developed this OPK guide so you know what to look for. We’ve also reviewed the most popular predictor kits on the market.

Keep reading to see what we found.

8 Best Ovulation Predictor Kit

Ovulation Test Strips

Similar to a pregnancy test that detect ovulation hormones in your urine. You’ll need a fresh urine sample to dip the stick in to. Some test strips give manual readings and other are digital. If using the cheap, manual test we recommend buying in bulk. That way you can test numerous times a day without it breaking the bank.

Best for:

  • Accuracy of around 97%
  • Using for only a few days of your cycle
  • Ease of use, simply dip into a urine same and await the results
  • Widely Available from pharmacies, drugstores, supermarkets and online


  • Manuals can be difficult to interpret
  • Cost can add up after a few cycles
  • Inaccurate results in women over 40
  • Don’t work if using injectable fertility drugs

Easy@Home Ovulation Test Strips

Pros: very low cost per test, easy to use, individually wrapped
Cons: thin, flimsy

For a very affordable option we highly recommend the Easy@Home Ovulation Test Strips. At around 25 cents per strip, you can test plenty without it breaking the bank. These are very easy to use, simply dip in a urine sample and read after 5 minutes. They are hygienic to use as individually foil wrapped, but you will need to provide your own sample cup.

Clearblue Digital Ovulation Test

Pros: Easy to read, easy to use, individually wrapped, sturdy test holder
Cons: expensive

The Clearblue Digital Ovulation Test is the best option if you struggle to interpret urine test results. At just under $2 per test they are the more expensive option. They work by placing individual tests into the test holder. The results take around 3 minutes and will show a smiley face if you are ovulating. This indicates you have a fertile window for 48 hours, so get baby dancing. Technically the test holder is ‘disposable’ after the 20 sticks are done. However a top tip to save money is to use the refill strips for the clear blue fertility monitor which will also work with this.

Read: When to Take a Pregnancy Test

Fertility Monitor

A fertility monitor is like a mini computer to alert you when you are fertile. These work by using urine test strips or measuring basal temperatures. The results are digital and will give a clear ‘yes’ or ‘no’ if you are ovulating. These machine are very easy to use on only require you to test once a day. A study found that women who use fertility monitors are 33% more likely to fall pregnant than any other OPK method.

Best for:

  • Clear results without the guesswork
  • Women who ovulate irregularly
  • Couples who have been TTC for a long time
  • Using before opting for expensive fertility treatment


  • May not be compatible with some medical conditions
  • Expensive outlay
  • Requires upkeep (batteries, test strips)
  • Can take a few months to calculate your ‘average’ cycle

Lady-Comp Fertility Monitor

Pros: Accurate, natural, no need for refills, quick use,
Cons: Very expensive, not for shift workers

The Lady-Comp Fertility Monitor is the most accurate ovulation predictor on the market. There is no need to buy any refills as it work by taking your oral or vaginal temperature. Insert the thermometer for 30 seconds and it will instantly tell you if you’re fertile or not. The thermometer will usually give a 6 day fertility window to maximise you chances of pregnancy. It’s a great alternative to manual thermometer charting which can be tricky to interpret. At just over $400 it’s a big investment to make, but it will last a life time.

Clearblue Fertility Monitor

Pros: Very easy to use, easy to read results, accurate, sturdy, convenient
Cons: expensive, requires urine stick refills

The Clearblue Fertility monitor is the best option for ease of use. You are only required to test for a short part of your cycle, so no need for daily testing. It’s great solution for shift workers who can’t always take temperatures at the same time each day. It works the same as a urine OPK but the computer analyses the results for you in 5 minutes. You will need to buy urine test strips every few months depending on how often it requests a test.

Basal Thermometer

Basal body temperature thermometers are specifically designed to track ovulation. These thermometer are design for internal use (oral or vaginal) with precision results. Result need taking the same time daily and before getting out of bed. You will need to track the results online, with an app or good old fashioned pen and paper. The pattern of the graph will show you when you have ovulated.

Best for:

  • Low cost
  • Very easy to use
  • Very accurate with correct technique
  • Women with irregular cycles


  • Needs battery upkeep
  • Inconvenient as requires daily routine
  • Not great for shift workers
  • Can require a few months for cycle pattern to emerge
  • Illness can alter results

Starlight and Sunny Basal Thermometer

Pros: inexpensive, lightweight, easy to read, soft beep, recall, auto shut off
Cons: inflexible tip, temperamental when battery is low

The Starlight and Sunny Basal Thermometer is a highly recommended thermometer for ovulation tracking. A reading takes around 1 minute and the results are given to a very precise 2 decimal points. The readings are in Fahrenheit (89.6 – 107.6) which is best for fertility tracking. The low light and soft beep are ideal for easy reading without disturbing your partners sleep. If you are forgetful or sleepy it has a recall button for your last reading. The kit comes with a paper chart if you like to manually chart your temps.

Iproven BBT 113

Pros: compact, easy to use, inexpensive, quiet beep, very accurate
Cons: no back light

The Iproven BBT 113 is the most accurate basal thermometer available. It take around a minute to get a reading for the most accurate results. The temperature is displayed at a very precise 2 decimal points. The thermometer will auto shut off after 5 minutes and can recall the last reading if you fall asleep. The beep is quite low, ideal for using first thing in the morning. The only downside was there was no back light which made it harder to read if the room was still dark.

Saliva Ferning

A small handheld microscope is uses to detect changes in your saliva. When you are fertile you will see a pattern which look similar to a curved fern leaf. The microscope needs to be at least 60-100 times magnification to detect any changes. Accuracy will depend on how experienced you are at analysing the patterns.

Best for:

  • Convenient to use day or night, as many times as you want
  • Very easy to use
  • Affordable, lifetime use and doesn’t require upkeep
  • Very discreet and can be used anywhere
  • Detects Estrogen surge – giving you a 3-4 day fertility window


  • Results can be difficult to interpret
  • Wait at least 30 minutes after eating before use
  • May need to use other OPK to confirm results
  • Not suitable for poor eyesight

KNOWHEN Saliva Fertility Monitor

Pros: Easy to use, includes free tracking app, convenient, one time purchase
Cons: difficult to interpret for beginners

The KNOWHEN Saliva Fertility Monitor is a high quality saliva microscope. It easy to use all you need is a small saliva sample. You wait 15 minutes for it to dry and then analyze the pattern. The kit comes with a handy booklet which shows you what to look for. It’s a bit of a learning curve at first but easy once you know what to look for. The results are around 98% accurate and a great methods to use alongside temp charting, mucous checking or urine test strips. We love how in touch this method makes you feel with your body.

Fertile Focus Ovulation Microscope

Pros: Easy to use, light, small, discreet, lightweight, inexpensive
Cons: unable to replace battery or light bulb, lens is awkward to remove for cleaning

The Fertile Focus Ovulation Microscope is the bestselling option on Amazon. It’s really easy to use with a small saliva sample. Upon analysing you should see distinctive pattern which will indicate if you are fertile or not. This kit does not tell when you are ovulating, just the window of opportunity. There is a lot of trial and error to use, but it works well once you know how. The downside was that if the battery or light goes you can’t replace and need to buy a new unit.

Ovulation Predictor Kit Basics

Buying Guide

When buying an ovulation predictor kit there is a lot of choice. These are Stork Mama’s buying tips to help you narrow down the selection to find the best OPK for you.

Detection – OPKs use various ways to give you a fertility window. Some will give you a 6 day window and others a 12-14 hour window. Tracking over your cycle will show when you have already ovulated.

Frequency – Consider how often you will need to test. Some methods such as temp charting require you to test daily. Others are such as saliva ferning or urine strips can be used a frequently as you want.

Convenience – Consider your lifestyle and I the method will work for you. If you’re a shift worker or like your sleep then charting isn’t a great option for you. You may also want to consider options which are portable or discreet to use.

Method – Fertility monitors will require you to test your urine, body temperature or saliva. Choose the method you are most comfortable with. All methods are accurate if analysed correctly. However not all methods are suitable for everyone e.g. those using fertility drugs, over 40’s.

Ease of Reading – Some methods will require you to manually analyse the result. This can cause a bit of ambiguity and leave you unsure. Digital methods will give you a clear yes or no answer and make it clear when you are most fertile.

Price – There is a huge variation in cost with OPKs from a dollar to hundreds of dollars. The cheapest methods are temperature charting or saliva ferning. Fertility monitors are a big investment and not suitable for those on a budget. If the method is single use only you will need to stock up on the kit for each cycle.

Low tech OPKs will not work for everyone, you may need to seek professional treatment. It can be a bit of trial and error to find a predictor kits which will work best for you.

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Benefits of OPKs

Improve chances of conception

Using OPKs will give you a window of opportunity in order to conceive. Women who track there cycle with OPKs are 33% more likely to get pregnant than those who don’t.


Using signals your body natural gives off during fertile time is a great way to get in touch with your body. These is no need for medication, just an understanding of signs of ovulation.

Avoid Fertility Treatment

OPKs were developed to aid fertility treatment, but they are so easy to use they can help anyone TTC. Tracking your cycle you can give you information you would have never known otherwise, such as early or late ovulation.


Even once you’ve had a baby you can use OPKs as a contraception method. It won’t protect you against STD’s but if used correctly it can be a non-medicated contraceptive option.

Disadvantages of OPKs


Don’t tell you exactly when you will ovulate, just an estimated window of opportunity. Some methods will indicate when you have already ovulated but it may be too late by then.

False Positives

Some unexpected changes such as stress, illness, fertility drugs or medical conditions can affect the results. This can give you inaccurate readings for a whole cycle and throw your tracking off course.

Frequent Use

Too much information can sometime be dangerous. Frequent testing can cause you to overthink or become obsessed about the results. This may cause you stress or anxiety and make it harder for you to get pregnant.

OPK Methods

Ovulation predictor work by detecting hormones in the body. Each method has its own benefits and drawbacks. Let’s explore each type and find the style best suited to you.

Estrogen Detection

Estrogen is released at the start of your cycle and rises until you ovulate. High levels of estrogen indicate that you will be most fertile over a 4-6 day period. This gives you a few opportunities to have sperm available as soon as the egg is released. Unfortunately there can be a few estrogen surges if you have long or irregular cycles. Methods which detect estrogen are saliva ferning, fertility monitors and temperature charting.

Luteinizing hormone (LH) Detection

Rising estrogen levels trigger the brain to release this hormone. Once this hormone is detected by an OPK you usually have a window of 12-36 hours before ovulation occurs. LH detection has a great accuracy at detecting your peak fertile day. However it often requires impromptu sex in order to avoid missing the narrow fertility window. LH surges can still happen whether an egg is released or not. Methods which detect LH levels are urine strips and fertility monitors.