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LineCheck

Ovulation test reader

Scan each LH strip and see when your surge is coming.

LineCheck ovulation test result showing Peak, a line ratio of 1.19 and the Low, Rising, High and Peak line stages
LineCheck calendar on cycle day 15 showing the fertile window, estimated ovulation and saved tests

How it works

  1. Scan your strip

    From the camera or your photo library.

  2. Get a ratio

    Test line measured against the control line.

  3. See the pattern

    Each day on your calendar and trend chart.

Watch an LH surge build

Scroll through one cycle’s ovulation strips.

Line ratio

0.18

Low

Day 1

Illustration of a typical surge. Always check your test’s instructions.

Cycle tracking

  • Fertile window

    Estimated from your cycle history.

  • LH trend charts

    Last 7 or 30 days, this cycle or the last.

  • Daily comparisons

    Darker or lighter than yesterday.

  • Cycle signals

    BBT, cervical mucus and symptoms.

  • Test reminders

    At the times you choose.

  • Apple Health

    Optional sync for your cycle data.

A positive LH test shows a surge, not that ovulation happened. Estimates can be wrong, and ovulation tests aren’t contraception.

Questions

What is the LH line ratio?

It's the strength of the test line divided by the strength of the control line on the same strip. A ratio around 1 or higher means the test line is as dark as or darker than the control, which most LH test brands treat as a positive. Because both lines are on the same photo, the ratio is steadier than judging darkness alone.

When should I start using ovulation tests?

It depends on your cycle length, so follow your test's instructions. LineCheck's calendar estimates your fertile window from your cycle history, and you can set reminders to test each day as it approaches.

I got a peak — when will I ovulate?

The LH surge usually comes about a day to a day and a half before ovulation, according to the US Food and Drug Administration. That's a typical pattern, not a guarantee for every cycle.

Why do my ovulation tests never reach peak?

Some surges are short and fall between tests, so testing once a day can miss them — some people test twice a day around their expected surge. Diluted urine, testing at a different time each day, irregular cycles and some health conditions can also affect results. If you're concerned, speak to a healthcare professional.

Can I use LineCheck to avoid pregnancy?

No. Ovulation tests and LineCheck's estimates are not reliable as contraception.

Scan your next ovulation test with LineCheck

Available on iPhone and iPad.

Android coming soon