Ovulation Calculator
Calculate your ovulation day and fertile window based on your last menstrual period and cycle length. Identify up to 6 fertile days each month for conception planning.
Clomid Ovulation Calculator
Estimate ovulation timing, fertile-window timing, and cycle milestones when taking Clomid (clomiphene citrate).
⚕️ Medical Disclaimer: This calculator provides estimates only. Clomid (clomiphene citrate) should only be used under medical supervision. Actual ovulation timing varies between individuals and cycles.
Average menstrual cycle length
days
Which Clomid cycle (1-6)
Day 3 FSH level
mIU/mL
Clomid Days⧉
Day 3–7
Take 50mg daily for 5 days
Expected Ovulation⧉
Day 12–17
Most likely around Day 15
Fertile Window⧉
Day 10–18
Best days for intercourse or IUI
LH Surge Testing⧉
Start Day 10
Begin OPK testing from this day
Ovulation Rate⧉
52%
Chance of ovulating at 50mg
Per-Cycle Pregnancy Rate⧉
8.0%
Cycle 1 at current dose
Cumulative Pregnancy Rate⧉
8.0%
After 1 cycle(s)
Progesterone Test⧉
Day 22
Confirm ovulation (target >3 ng/mL)
Cycle Timeline
| Event | Cycle Day(s) | Notes |
|---|---|---|
| Period Start | Day 1 | First day of menstrual bleeding |
| Baseline Labs | Day 2–3 | FSH, estradiol, ultrasound |
| Start Clomid | Day 3 | 50mg daily |
| Last Clomid Pill | Day 7 | 5 consecutive days completed |
| Start OPK Testing | Day 10 | Test daily until positive |
| Fertile Window Opens | Day 10 | Begin timed intercourse |
| Expected Ovulation | Day 12–17 | Peak around Day 15 |
| Progesterone Test | Day 22 | 7 DPO confirmation |
| Pregnancy Test | Day 29 | 14 DPO (if period late) |
| Expected Period | Day 28 | If not pregnant |
Clomid Success Rates by Dose
50 mg
Ovulation
52%
Pregnancy
8%/cycle
100 mg
Ovulation
72%
Pregnancy
10%/cycle
150 mg
Ovulation
80%
Pregnancy
12%/cycle
Planning notes, formulas, and examples
About the Clomid Ovulation Calculator
Clomid (clomiphene citrate) is one of the most commonly prescribed fertility medications. It works by stimulating the pituitary gland to release more FSH and LH, which can trigger ovulation. The Clomid Ovulation Calculator is a timing worksheet that estimates when ovulation is most likely to occur based on your dosing schedule, cycle length, and a few background factors.
Ovulation typically occurs 5–10 days after the last Clomid pill, creating a narrower timing window for cycle planning. This calculator maps out a typical cycle timeline: the estimated ovulation window, fertile days, a common OPK-testing window, and when clinicians often check a luteal-phase progesterone level.
Understanding your Clomid cycle timeline can make cycle planning easier, but this page is still only a timing estimate. The calculator also shows broad per-cycle and cumulative pregnancy-rate context based on dose and cycle number rather than individualized fertility odds.
When This Page Helps
Clomid treatment often involves a narrower ovulation window than an unmedicated cycle. Knowing when ovulation commonly occurs helps with OPK timing, intercourse or IUI planning, and follow-up blood-work timing.
This calculator reduces some of the guesswork by laying out a day-by-day timing estimate. It also gives rough success-rate context, but it should not be treated as an individualized fertility prognosis.
How to Use the Inputs
- Enter your average menstrual cycle length (typically 26–35 days).
- Select your prescribed Clomid dose (50mg, 100mg, or 150mg).
- Choose your dosing protocol (Days 3–7 or Days 5–9).
- Enter which Clomid cycle you are on (1st through 6th).
- Input your baseline Day 3 FSH level if known.
- Review the predicted ovulation window and fertile days.
- Use the timeline table as cycle-planning context, not as a substitute for your fertility clinician’s instructions.
Formula used
Expected Ovulation = Last Clomid Day + 5 to 10 days
Fertile Window = Ovulation Day - 2 to Ovulation Day + 1
Progesterone Test = Ovulation Day + 7
Pregnancy Test = Ovulation Day + 14Example Calculation
Result: Ovulation Day 12–17, Fertile Window Day 10–18
On a Days 3–7 protocol, the last pill is taken on Day 7. Ovulation is expected 5–10 days later (Days 12–17), with the fertile window spanning Days 10–18.
Tips & Best Practices
- Many patients take Clomid at the same time each day; bedtime is often used when hot flashes or nausea are bothersome.
- Some clinicians pair OPKs with basal-body-temperature or ultrasound monitoring to confirm ovulation timing more confidently.
- A mid-luteal progesterone level is commonly used to confirm that ovulation likely occurred.
- Side effects like hot flashes, mood swings, and bloating are common but usually mild.
- Do not exceed 6 cycles of Clomid due to a potential increased risk of ovarian cancer with prolonged use.
How Clomid Works
Clomid (clomiphene citrate) is a selective estrogen receptor modulator (SERM) that blocks estrogen receptors in the hypothalamus. This tricks the brain into thinking estrogen levels are low, prompting increased secretion of GnRH, FSH, and LH. The resulting FSH surge stimulates the ovaries to develop follicles, while the LH surge triggers ovulation.
The medication is typically taken for 5 days early in the menstrual cycle. The Days 3–7 protocol may produce more follicles, while the Days 5–9 protocol may result in a single dominant follicle that grows larger, potentially leading to better endometrial lining.
Monitoring Your Clomid Cycle
Proper monitoring is essential for Clomid treatment success. Your doctor may recommend baseline blood work (Day 3 FSH and estradiol), mid-cycle ultrasound to check follicle development, and a Day 21 progesterone test to confirm ovulation. At-home monitoring with OPKs and basal body temperature charting can supplement clinical monitoring.
If you are having IUI, timing is especially important, but the exact insemination plan should come from the monitoring strategy used by your fertility clinic.
When to Consider Next Steps
If pregnancy has not happened after several monitored cycles, clinicians often review whether the issue is ovulation, sperm, tubal factors, age-related egg quality, or a different fertility diagnosis. That broader review is usually more useful than repeating the same timing worksheet indefinitely.
Sources & Methodology
Last updated:
Methodology
This worksheet uses the usual post-clomiphene ovulation window, dose schedule, and follow-up timing to estimate fertile-window context. It is a timing aid for cycle planning, not a substitute for monitored fertility care.
Sources
- Clomiphene citrate prescribing information (FDA) — Official label for clomiphene dosing, timing, and warnings.
- Ovulation induction (ASRM) — Clinical guidance on clomiphene use and cycle timing.
Frequently Asked Questions
Many clinicians start OPK testing about 2-3 days after the last Clomid pill. For a Days 3-7 schedule, that often means beginning around Day 10, but the exact timing can vary by cycle response and monitoring plan.
Clomid can cause false-positive OPK results if you test too soon after the last pill. Wait at least 3 days after finishing Clomid before trusting OPK results.
About 8–12% per cycle for conception, with an 80% cumulative rate of ovulation over multiple cycles. The pregnancy rate per ovulatory cycle is about 15%.
Many clinicians review the plan after 3-6 Clomid cycles, especially if ovulation is not occurring or pregnancy has not happened despite monitored cycles. The next step depends on age, diagnosis, semen analysis, tubal status, and the broader fertility workup.
Higher doses may shift ovulation slightly later in the cycle. The 5–10 day window after the last pill remains the general guideline regardless of dose.
Your doctor will likely increase the dose to 100mg and then 150mg in subsequent cycles. About 50% of women who fail to ovulate at 50mg will respond to a higher dose.
More in this topic
Menstrual Cycle Tracker Calculator
Track your menstrual cycle phases — follicular, ovulatory, and luteal. Predict next period date, PMS window, and cycle regularity from your average cycle length.
BBT (Basal Body Temperature) Calculator
Track your basal body temperature for fertility awareness. Estimates ovulation day, cycle phase, fertility window, thermal shift detection with the 3-over-6 rule, and cycle timeline visualization.