The Short Version
All four are budget dip-strip LH tests, and they work the same basic way: dip, wait, compare the test line to the control line. The real differences are in how you read them. Wondfo (manufacturer-stated 25 mIU/mL) and Pregmate (25 mIU/mL) are no-frills line strips, with Pregmate adding an app scanner and a numeric version. Easy@Home is a classic line strip that the Premom app turns into a test-to-control (T/C) ratio. Premom Quantitative strips are scanned by the app to estimate an LH number (0–65 mIU/mL). Regular cycles and you like simple: Wondfo or Pregmate. You want a chart: Easy@Home or Pregmate with the app. Irregular cycles, low or confusing surges: a numeric option (Premom Quantitative or Pregmate Numeric).
In this article
Ovulation predictor kits (OPKs) are the single best-value tool in early TTC, and the cheapest ones are often strips sold by the dozen. But “cheap” doesn't mean interchangeable. The four brands people compare most share a format and differ in how much help they give you reading the result. Here's what each manufacturer actually states — and where they don't say.
How cheap OPK strips work
OPK strips detect luteinizing hormone (LH) in urine. LH is always present at a low level — Premom notes it's common to have low LH throughout the cycle — and then surges shortly before ovulation. ASRM's committee opinion notes ovulation may occur any time within the 2 days after the urinary LH surge.
A strip has a control line (proves the test worked) and a test line whose darkness reflects LH. On standard strips, the test line usually shows up faintly most days. Premom's guidance states the common rule: a result is only positive when the test line is as dark as, or darker than, the control line. A faint line just means LH is present, not peaking.
Sensitivity here means the LH concentration at which a strip is designed to turn positive. A 25 mIU/mL strip needs urinary LH around that level before the test line matches the control.
The four compared
| Wondfo | Pregmate | Easy@Home | Premom Quantitative | |
|---|---|---|---|---|
| Format | Dip strip (also cassette and midstream) | Dip strip | Dip strip | Dip strip |
| Manufacturer-stated LH sensitivity | 25 mIU/mL | 25 mIU/mL (standard and numeric strips) | Not stated on the manufacturer pages we reviewed | Not stated as a cut-off; app estimates LH from 0–65 mIU/mL |
| How you read it | By eye: test vs control line | By eye, or scan in the Pregmate app; numeric version gives a number | By eye, or scan in the Premom app for a T/C ratio | Scan in the Premom app for an estimated LH value |
| Positive means | Test line as dark as or darker than control | Standard: line comparison; Numeric: 25 or above | Line comparison; app T/C ratio of 0.8+ flagged as surge | App flags rising LH from 12.5 mIU/mL and tracks the peak |
| Reading time | Per package insert | 5 minutes | Per package insert | 5–10 minutes |
| Who makes it | Guangzhou Wondfo Biotech | Pregmate | Easy Healthcare | Easy Healthcare |
All figures are as stated by each manufacturer as of October 2026. We left a cell blank rather than repeat numbers we couldn't confirm on a manufacturer page. Prices change daily and vary by pack size; all four sit in the budget tier compared with digital OPKs.
Brand by brand
Wondfo: the plain workhorse
Wondfo's own product page lists its One Step Ovulation Urine Test at 25 mIU/mL, in strip, cassette, and midstream formats, as a qualitative test for predicting the LH surge. There's no app ecosystem to speak of — you read the line yourself, which is perfectly adequate if your cycles are regular and your surges are clear.
Good for: regular cycles, lowest-fuss testing, people who don't want another app. Compare Wondfo strips on Amazon.
Pregmate: line strips with an optional app
Pregmate's product page lists its standard ovulation strips at 25 mIU/mL, as a dip strip with results in 5 minutes, sold in packs of 25, 30, 50, and 100. You can scan strips in the Pregmate app, which shows how dark the test line is and saves each scan. Pregmate also sells numeric LH strips, also listed at 25 mIU/mL, where the company says a reading at or above 25 means the surge has started and ovulation is likely within 24–48 hours.
Good for: people who want cheap line strips now with the option to add structure later. Compare Pregmate strips on Amazon.
Easy@Home: the classic, app-charted
Easy@Home and Premom are both made by Easy Healthcare, and Premom describes both as FDA-cleared LH tests. Easy@Home strips are qualitative: you compare lines, and if you scan them, the Premom app converts the image into a T/C ratio, flagging a surge at a ratio of 0.8. We couldn't find a sensitivity figure on the manufacturer pages we reviewed, so we haven't listed one. Premom describes the two brands as having “comparable sensitivity.”
Good for: people who want an automatic chart and like seeing the trend, not just a yes/no. We go deeper in Premom vs Easy@Home. Compare Easy@Home strips on Amazon.
Premom Quantitative: an estimated number
Premom's quantitative strips are designed to be scanned: the company says to dip for 5–10 seconds, read in 5–10 minutes, then scan with the app, which estimates LH levels from 0 to 65 mIU/mL and charts them. Premom says its app treats 12.5 mIU/mL as the threshold for rising LH. The value is an app estimate from an image, not a lab measurement — useful for spotting your pattern, especially if your surge is short or modest.
Good for: irregular cycles, suspected low or multiple surges, people who find line-shade comparisons stressful. Compare Premom Quantitative strips on Amazon.
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Getting accurate results from any strip
- Start on the right day. Clearblue's ovulation-test leaflet gives a sensible rule that works for any brand: if your cycle varies, use the shortest cycle from your last six to decide when to start; if you don't know your cycle length, track one cycle first. The ovulation calculator can help.
- Test at a consistent time. Premom's Q&A says it normally recommends testing between about 10 a.m. and 5 p.m. Pick a time and stick with it.
- Follow the insert's dip time and reading window. Over-dipping or reading late can distort lines.
- Test once or twice a day near your expected surge. Surges can be brief; a twice-daily routine catches more of them.
- Compare against the control line, not yesterday's strip. Photos help, but lighting changes everything.
- Act on the first positive. ASRM says intercourse every 1–2 days during the fertile window is most efficient — and the window opens before the surge, so don't wait for a strip to start trying.
When strips mislead
Every OPK, cheap or not, reads hormone levels — not ovulation itself. ASRM notes that LH kits have false-positive results in about 7% of cycles. Clearblue's leaflet lists situations that can give misleading results, including:
- Polycystic ovary syndrome — Premom has a whole explainer on why people with PCOS can see multiple darker lines in one cycle, so confirm with temperature charting.
- Pregnancy or recent pregnancy — hCG resembles LH and can trigger a “positive.” See OPKs after a miscarriage.
- Fertility drugs containing LH or hCG, and Clomid, which Clearblue says may give misleading results on some readings.
- Recently stopping hormonal contraception or recent pregnancy: Clearblue advises waiting two cycles before relying on its tests.
- Having reached menopause.
If your strips are confusing, adding basal body temperature charting confirms whether ovulation actually followed a surge — see Natural Cycles vs Tempdrop. Postpartum? Read tracking ovulation while breastfeeding first.
Which to buy
| Your situation | Good fit | Why |
|---|---|---|
| Regular cycles, want simple and cheap | Wondfo or Pregmate standard | Stated 25 mIU/mL; read by eye; no app needed |
| Want a chart without paying for numbers | Easy@Home (with Premom app) or Pregmate (with its app) | App scans add structure to line reading |
| Irregular cycles or confusing surges | Premom Quantitative or Pregmate Numeric | An estimated number shows rises and peaks more clearly than line shades |
| Hate interpreting anything | Consider a digital OPK instead | Costs more per test, but shows a symbol rather than lines; see Clearblue vs Easy@Home |
The bottom line
For most people with regular cycles, any of these will find the surge. Wondfo and Pregmate both state 25 mIU/mL on their own pages; Easy@Home and Premom don't publish a single cut-off but pair their strips with an app that does the reading for you.
Choose by how you want to read results, not by tiny price differences: by eye, by ratio, or by an estimated number.
And if several well-timed cycles pass without success, the strips have done their job — it's time for a basic workup. Our guide on when to see a fertility doctor covers the timing.
Frequently asked questions
What sensitivity are Wondfo and Pregmate ovulation strips?
Both manufacturers list 25 mIU/mL. Wondfo states 25 mIU/mL for its One Step Ovulation Urine Test, and Pregmate states 25 mIU/mL for both its standard and numeric ovulation strips.
Are Easy@Home and Premom the same company?
Yes. Premom states that Easy@Home and Premom are both made by Easy Healthcare and describes both as FDA-cleared LH tests. Easy@Home strips are read as lines or a T/C ratio, while Premom Quantitative strips are scanned for an estimated LH value.
How do I know if my ovulation strip is positive?
On standard strips, a result is positive when the test line is as dark as, or darker than, the control line. A faint test line is normal and just means some LH is present. Numeric strips use a set value instead, such as 25 or above on Pregmate Numeric.
Are cheap OPK strips as accurate as Clearblue?
They detect the same hormone and, when used correctly, can identify the LH surge. The main difference is how results are read: digital tests show a symbol, while strips need you or an app to compare lines. Any OPK can mislead with PCOS, recent pregnancy, or certain fertility drugs.
What time of day should I use ovulation strips?
Follow your brand's insert. Premom says it normally recommends testing between about 10 a.m. and 5 p.m.; whichever brand you use, test at a consistent time each day. Testing twice a day near your expected surge helps catch short surges.
Sources
- Wondfo — One Step Ovulation Urine Test (product page)
- Pregmate — Ovulation Test Strips
- Pregmate — Ovulation Test Strips with Numeric Results
- Premom — Premom vs Easy@Home ovulation tests
- Premom — Quantitative LH Ovulation Test Strips (product page)
- Premom — Questions & Answers: Premom Quantitative Tests (PDF)
- Premom — Faint line on ovulation test: what it means
- Premom — Multiple positive ovulation tests with PCOS
- Clearblue Advanced Digital Ovulation Test — leaflet (PDF)
- ASRM Practice Committee — Optimizing natural fertility: a committee opinion (Fertil Steril, 2022)
Product details and prices reflect manufacturer information checked in October 2026 and change often — always confirm current instructions, pricing, and return policies with the manufacturer before buying. This article is educational and is not medical advice.