Hamster pregnancy guide
How long is a hamster pregnant?
A hamster is pregnant for about 16 days. The normal range is 15 to 18 days, so most pups arrive within that window rather than on the exact average day. Breed shifts the date by a few days, which is why the calculator asks for it.
Quick rule: Count 2 weeks forward from the mating date. The birth window runs from day 15 to day 18.
How to use the hamster pregnancy calculator
1. Enter the mating date. The day she was put with the male. Tap Use today if it was today.
2. Pick the breed. The whole window moves with the breed average.
Then follow the schedule. Each task gets a real date, the next one is highlighted, the status shows whether your female is on track, and the week by week cards above show where things stand. Use Copy schedule or Add to Google Calendar to keep it.
Gestation formulas
- Estimated birth date = mating date + 16 days
- Earliest normal birth = mating date + 15 days
- Latest normal birth = mating date + 18 days
- Breed adjustment = breed average minus 16 days, applied to the whole window
- Call your vet if nothing has happened by day 19
Care schedule for a pregnant female
| When | Task | Why |
|---|---|---|
| Day 10 | Full cage clean | Clean thoroughly now. Avoid disturbing her after this. |
| Day 12 | Extra food and nesting | Add extra protein and unscented paper bedding. |
Signs of birth and when to call the vet
Labour is close if she has
- ✓Heavy nest building
- ✓Hoarding food
- ✓Restless, then hiding in the nest
- ✓Belly suddenly smaller
Call your vet immediately if
- !Strong straining for 30 minutes with no pup born
- !A baby is visible but stuck, or comes backwards with no progress
- !Heavy bleeding or foul-smelling discharge
- !She is weak, collapsed, off her food or in obvious pain
- !No birth by day 19
Hamster gestation by breed
| Breed or type | Average | Normal window from the start date |
|---|---|---|
| Syrian hamster | 16 days | 15 to 18 days |
| Dwarf, Campbell or Winter White | 20 days | 19 to 22 days |
| Roborovski | 21 days | 20 to 23 days |
Frequently asked questions
How long is a hamster pregnant?
A hamster is pregnant for about 16 days. Most pups arrive between day 15 and day 18. Breed matters: Syrian hamster about 16 days, Dwarf, Campbell or Winter White about 20 days, Roborovski about 21 days.
How accurate is this calculator?
It uses the average length and the normal range published in veterinary references, adjusted for the breed you pick. Individual animals vary, so treat the date as the middle of a window, not a promise.
What if she goes past the due date?
Going a few days past the average is normal. The calculator marks day 18 as the end of the usual window and day 19 as the point to call your vet even if she seems well.
What are the signs that birth is close?
Heavy nest building. Hoarding food. Restless, then hiding in the nest.
Is my data saved?
No. Everything is calculated in your browser. Nothing you type is stored or sent anywhere.
Disclaimer: This calculator gives estimates for planning only. It is not veterinary advice and cannot replace an examination by your vet. If you are worried at any stage, especially around birth, contact your vet promptly.
