Pregnant medium dog in late-stage pregnancy resting peacefully on a soft dog bed in warm muted light

Dog pregnancy & gestation calculator

Pick breeding date or ovulation date. The calculator gives a whelping window, current pregnancy week (or gestation day for breeders), and the vet checkpoints that matter — because dogs don't deliver on one guaranteed calendar square.

Updated May 25, 2026

Before you start

Planning checklist

Breeding date, if known
Ovulation or progesterone date, if tested
Today's date
Whether pregnancy is confirmed
Any symptoms or labor signs
Vet contact saved

Dog pregnancy calculator

Pick the date she was bred or ovulated. We compute the whelping window, the gestation week she's in, and what's happening in there right now.

Reference eventbreeding (broader window) or ovulation (tight)

DateYYYY-MM-DD

Mid-range due date

June 27, 2026

Whelping window: June 22, 2026 to July 2, 2026. Smaller breeds tend earlier, larger breeds later.

Right now — day 30 of ~63

Week 5 — palpation possible

Vet abdominal palpation feasible around day 28-30 — fetuses feel like firm grapes (small dogs) or golf balls (large dogs). After day 35 the uterus fills with fluid and palpation becomes unreliable; switch to ultrasound or radiograph.

33 days to mid-range due date.

Week-by-week timeline

Week 1 — fertilizationday 0-6
Embryos travel down the oviducts toward the uterus. No outward signs of pregnancy yet. The dog can still be bred — kennel mismatings are caught here if at all.
Week 2 — embryos arrive in uterusday 7-13
Embryos reach the uterine horns and begin to implant. Still no visible signs to an owner; some dogs show mild appetite changes.
Week 3 — implantation completesday 14-20
Embryos finish implanting. Ultrasound can detect pregnancy starting around day 21-25 — earliest reliable confirmation window.
Week 4 — heartbeats detectableday 21-27
Fetal heartbeats become detectable on ultrasound. Organogenesis is underway. Morning sickness may appear briefly. Avoid all medications and vaccines unless vet-approved.
Week 5 — palpation possibleday 28-34
Vet abdominal palpation feasible around day 28-30 — fetuses feel like firm grapes (small dogs) or golf balls (large dogs). After day 35 the uterus fills with fluid and palpation becomes unreliable; switch to ultrasound or radiograph.
Week 6 — skeletal calcificationday 35-41
Fetal skeletons begin to calcify. Body shape changes become visible to the owner. Increase the dog's calorie intake gradually — by week 9 she'll need 1.5-2× maintenance kcal.
Week 7 — radiographic visibilityday 42-48
Fetal skulls visible on x-ray around day 45 — most accurate count of puppies in the litter. Hair coats begin developing on the puppies. Set up the whelping box and let the dog acclimate.
Week 8 — movement detectableday 49-55
Puppy movement becomes visible through the abdominal wall. Mom's appetite may drop temporarily as the uterus crowds the stomach. Switch to multiple small meals.
Week 9 — whelping windowday 56-62
Birth typically occurs between days 58-68 (anchored to breeding) or 61-65 (anchored to ovulation). Watch for: rectal temperature drop below 100°F (38°C), restlessness, nesting, refusing food. Active labor follows 12-24 hours after the temperature drop.

The math

Reference: breeding date = 2026-04-25. Mid-range gestation = 63 days; published window = 58-68 days (10-day window — sperm can persist 5-7 days).
30 days into gestation; 33 days to mid-range due date (2026-06-27).
Whelping window: 2026-06-22 (earliest) to 2026-07-02 (latest). Smaller breeds trend earlier; larger breeds later.
Source: AKC dog reproductive cycle reference + Merck Vet Manual canine reproduction. Individual dogs vary — confirmation by vet ultrasound (day 21-30) or radiograph (day 45+) is the reliable read.

Calculator output is an estimate, not a guarantee. Confirmation of pregnancy and litter size needs vet ultrasound (day 21-30) or radiograph (day 45+). Whelping is the dog's call, not the calendar's.

AKC·Merck Vet Manual·VCA

Why this is a window, not a due date

Canine pregnancy is about 63 days from ovulation¹. The complication for most owners: ovulation isn't directly visible at home. What you usually have is a breeding date, and breeding can happen up to about a week before the actual conception event because sperm survives in the uterus while it waits for ovulation¹. That uncertainty widens the whelping window from a roughly 4-day spread (anchored to ovulation) to a roughly 10-day spread (anchored to breeding).

Progesterone or other ovulation-timing blood tests at the vet narrow the estimate by catching ovulation directly¹. The calculator above asks which reference point you have, then outputs a date range — not a single calendar square. That range is the honest read.

Breeders working from a known ovulation date can read the same output as a day-by-day gestation timeline — same engine, same 63-day model, just shifted from owner-friendly week labels to the breeder-standard day count.

How to count the pregnancy

Count from the best reference date you have, then keep the uncertainty attached to that reference. A vet-confirmed ovulation date gives the tightest timeline. A breeding date is useful, but it is not the same as conception date because sperm can survive for several days before ovulation.

Day count

Day 1 is the day after the ovulation or breeding date you entered. Day 63 is the center of the ovulation-anchored due window, not a guarantee.

Week count

Week 1 is days 1-7, week 2 is days 8-14, week 3 is days 15-21. By week 4, ultrasound confirmation is usually the practical next step.

Day-by-day view

Once the anchor date is set, the calculator above also reads as a day-by-day gestation timeline — useful for breeders tracking the 63-day cycle to specific vet checkpoints.

Which date should you enter?

Match the date you actually have to the right mode. Each row tells you how tight the answer will be and what to do next.

Input you have	Use this mode	How accurate	What to do next
Ovulation or progesterone date from a vet	Ovulation mode	Tight (~4 days)	Plan ultrasound by day 28 if not yet done. X-ray for puppy count after day 45.
Known breeding date (single)	Breeding mode	Wider (~10 days)	Add an ultrasound around day 28 to confirm pregnancy and tighten the estimate.
Multiple breeding dates	Breeding mode, run earliest and latest	Widest — use the union of both windows	Ask the vet about retroactive dating with progesterone history or ultrasound fetal age.
Unknown date, suspected pregnancy	Skip the calculator for now	Not estimable yet	Book an ultrasound. It confirms pregnancy and gives a rough fetal age from day 21 onward.
Already near labor (within suspected window)	Either mode	Use signs, not the date alone	Track temperature and the early labor signs (below). Have the vet contact ready.

Week-by-week checkpoints

What's actionable for an owner at each stage. The timeline above shows the developmental side; this is the owner-side schedule.

Week 1-2. Fertilization happens after ovulation. No reliable home signs of pregnancy yet — early behavior changes are not specific.
Week 3-4 (day 21-30). Ultrasound window. A vet can usually confirm pregnancy from day 21-25 and see heartbeats from about day 25².
Week 5-6.Calorie needs start ramping up. Visible abdominal and mammary changes may appear, but they're not a substitute for a confirmed pregnancy.
Day 45+. Radiograph (x-ray) window for puppy count. Fetal skulls have calcified enough to count².
Day 58+. Whelping prep — set up the whelping box and begin twice-daily rectal temperature checks³.
Day 63 (the window, not the date). Inside the typical whelping window if anchored to ovulation. Anchored to breeding date, day 63 is the middle of a 10-day spread — labor may come earlier or later.
Day 70+ from breeding, or any concerning sign. Vet call. Day 70+ from breeding without labor is past the published range and worth evaluating³.

The three vet dates owners should remember

Three appointments do most of the work on a confirmed pregnancy.

1. Confirmation
Ultrasound — day 21 to 30
Confirms pregnancy and shows heartbeats. A rough fetal count is possible but not the final number².
2. Puppy count
Radiograph (x-ray) — day 45+
Fetal skulls have calcified by day 45. Knowing the count helps an owner recognize when the last puppy has been delivered².
3. Anything off
Vet call — labor signs abnormal or window exceeded
Hard contractions over 30 minutes without a puppy, more than 2 hours between puppies, green or black discharge before the first puppy, or day 70+ from breeding without labor³.

Labor signs: what owners often track vs when to call the vet

Common pre-labor signs owners often track

These are signs owners often see leading up to labor — not proof that labor is safe or progressing normally. If anything looks off, call the vet.

Nesting behavior
Appetite drop in the last day or two
Restlessness
Rectal temperature drop below 100°F (38°C)³
Panting
Mild clear discharge close to labor

Call the vet

Any one of these is a vet call, not a wait-and-see.

Hard contractions over 30 minutes with no puppy³
More than 2 hours between puppies³
Green or black discharge before the first puppy
Severe weakness, collapse, or fever
Obvious pain or distress
Pregnancy extends beyond the expected window
Puppy visible but stuck

Worked examples

How the same calculator reads three common situations.

Scenario 1

Known breeding date only

Use breeding mode. Expect a wider whelping window (about 10 days). Schedule ultrasound around day 28 to confirm pregnancy and tighten the estimate.

Scenario 2

Vet-confirmed ovulation

Use ovulation mode. Expect a tighter window (about 4 days). Schedule radiograph at day 45 for puppy count, then plan whelping prep around day 58.

Scenario 3

Multiple breeding dates

Run the calculator twice — once on the earliest date, once on the latest — and use the union of the two windows. Ask the vet whether progesterone history or ultrasound fetal age can narrow the conception date retroactively.

Questions worth asking

How long are dogs pregnant?

Canine pregnancy is about 63 days from ovulation — the figure the American Kennel Club and Merck Veterinary Manual both publish. Anchored to breeding date, the window is wider (usually 58 to 68 days) because sperm can persist in the uterus for several days waiting for ovulation. A whelping window is more honest than a single due date.

Is dog pregnancy 63 days from breeding or ovulation?

The 63-day figure is measured from ovulation, not breeding. Breeding can happen up to a week before the actual conception event because sperm survives in the uterus while it waits for ovulation. If a vet has confirmed ovulation through progesterone testing, the window is tight (about 61 to 65 days). If only breeding date is known, expect a roughly 10-day spread.

How accurate is a dog pregnancy calculator?

Accuracy depends on what date the calculator is anchored to. Ovulation date from progesterone testing narrows the whelping window to about 4 days. Breeding date alone widens it to about 10 days. A calculator that returns a single confident date from breeding date alone is hiding the natural uncertainty.

When can a vet confirm pregnancy?

The earliest reliable confirmation is ultrasound from day 21 to 25, which can show heartbeats. Abdominal palpation (a vet's hands-on belly check) around day 28 to 30 can also confirm pregnancy but becomes unreliable after day 35 as the uterus fills with fluid. Radiograph (x-ray) from day 45 onward gives the most accurate puppy count because puppy skulls have hardened enough to count.

When should I get an x-ray for puppy count?

Day 45 or later is the standard window. Before day 45, fetal skulls have not calcified enough to count reliably on radiograph. Knowing the count before whelping helps an owner recognize when the last puppy has been delivered.

How do you count dog pregnancy weeks?

Start from the reference date you actually know. From ovulation, day 1 is the day after ovulation and the usual due window centers around day 63. From breeding date, count the same calendar days but treat the result as wider because conception may have happened several days later. Week 1 is days 1-7, week 2 is days 8-14, and so on; by day 58 most owners should be in whelping-prep mode.

What labor signs mean I should call the vet?

Hard contractions lasting more than 30 minutes without a puppy. More than 2 hours between puppies after the first. Green or black discharge before any puppy has emerged. Severe weakness, collapse, or fever. Obvious pain or distress. A puppy visible but stuck. Pregnancy extending beyond the expected window. Any one of these is a vet call, not a wait-and-see.

Sources

Full source list with verbatim quotes lives at /methodology. Specific to this calculator:

1. American Kennel Club. Dog Reproductive Cycle. The 63-day gestation figure measured from ovulation, the sperm-survival window behind the wider breeding-anchored spread, and the role of progesterone / LH-surge timing in narrowing the estimate. akc.org dog-reproductive-cycle ↩
2. Merck Veterinary Manual. Pregnancy Determination in Bitches and Queens. Ultrasound (day 21-25), palpation (28-30), and radiograph (day 45+) confirmation windows. merckvetmanual.com pregnancy-determination ↩
3. VCA Animal Hospitals. Pregnancy and Parturition in Dogs. Temperature drop, stage-1/stage-2 labor signs, and dystocia thresholds. vcahospitals.com pregnancy-in-dogs ↩

Pairs with this calculator: the puppy weight calculator (adult-size predictor once the puppies arrive), and the dog calorie calculator (mom's elevated calorie needs in late gestation and lactation).

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