Dog progesterone levels chart and ovulation calculator
Enter the progesterone results from your vet or lab. The calculator shows the stage of each test, estimates the ovulation day, and gives the best days to breed and the due date. It uses the same method as the Sire & Dam app.
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Guidance only – always follow your vet. Values are averages from standard veterinary reproduction references; labs, breeds and dogs vary.
Dog progesterone levels chart
Progesterone starts to rise just before ovulation. Breeders and vets use a series of blood tests to find the day she ovulates, which is the key date for timing the breeding and for the due date (63 days later).
| Stage | ng/mL | nmol/L | What it means | Next step |
|---|---|---|---|---|
| Baseline | below 1.5 | below 4.8 | Anoestrus or early heat (pro-oestrus). | Test every 2–3 days. |
| LH surge | 1.5 – 3.9 | 4.8 – 12.4 | The LH surge is happening or just happened. Ovulation follows in about 2 days. | Test daily. |
| Ovulation | 4.0 – 9.9 | 12.7 – 31.5 | She is ovulating. The eggs need about 2 more days to mature. | Plan the breeding. |
| Fertile | 10 and above | 31.8 and above | After ovulation: the eggs are mature and fertile for the next few days. | Breed now, by method. |
1 ng/mL = 3.18 nmol/L. These are typical ranges. Labs and test methods (in-clinic analysers and reference labs) can read differently, so use your lab's reference ranges and stay with the same lab for the whole series.
How the ovulation day is estimated
- The first test of 4 ng/mL or more is taken as the ovulation day.
- If the tests have only reached the LH-surge range (1.5–3.9 ng/mL), ovulation is estimated as 2 days after the first test in that range. A test above 4 ng/mL confirms it.
- Example: 0.9 ng/mL on 1 March, 2.1 on 3 March, 5.4 on 5 March. Ovulation is 5 March, the best days for a natural mating are 6 to 9 March, and the due date is 7 May.
Best days to breed by semen type
| Method | Best days after ovulation | Why |
|---|---|---|
| Natural mating | Days 1–4 | Fresh semen lives for days in the female, so it can go in before the eggs are mature. |
| Fresh AI | Days 1–4 | Same as natural mating. |
| Chilled semen | Days 2–4 | Lives a little less long than fresh semen. |
| Frozen semen | Days 3–4 | Lives only hours after thawing, so it has to meet mature eggs. |
Frequently asked questions
When should I start progesterone testing?
Around day 5 or 6 of the heat (counting the first day of bleeding as day 1), then every 2–3 days. Once the result starts to rise, test daily or as your vet advises.
What progesterone level means ovulation in dogs?
Ovulation usually happens at about 4–8 ng/mL (roughly 12.7–25 nmol/L). The LH surge comes first, at about 1.5–3.9 ng/mL, about two days before ovulation.
How do I convert ng/mL to nmol/L?
Multiply by 3.18. For example, 5 ng/mL is 15.9 nmol/L. To go back, divide nmol/L by 3.18. The calculator does it for you when you pick the unit.
Can I rely on the calculator instead of my vet?
No. It shows the standard interpretation of a test series. Results depend on the lab and the dog, and your vet or reproduction specialist decides when to breed.
More free breeding tools
- Dog pregnancy calculator: whelping date and a day-by-day pregnancy timeline
- Dog heat cycle calculator: when the next heat is due
- Puppy weight gain calculator: checks whether a newborn puppy is gaining enough
- Sire & Dam app: heats, progesterone, pregnancies and litters in one place