How many months is 25 weeks pregnant?

25 weeks is roughly 5½ months. Months are an awkward unit in pregnancy because they do not divide evenly into weeks — a calendar month averages about 4.3 weeks, which is why 40 weeks works out a little over nine months rather than ten. Appointments and scans are always booked in weeks, so weeks are the figure worth carrying.

How big is a baby at 25 weeks?

The NHS publishes around 34.6 cm long, from head to heel for week 25. Rather than one fruit, that length is offered here against eight rulers, each object carrying its own measurement: a giant Easter egg (35 cm top to bottom), a galah (35 cm beak to tail), Tickle Me Elmo (35 cm head to feet), a tennis racquet's head (33 cm tip to throat), and four more. Published lengths are averages across many babies, not a measurement of any particular one, and a scan estimate that differs is a normal thing rather than a finding.

What trimester is 25 weeks?

Week 25 is in the second trimester, on the commonly published split of weeks 1–12, 13–26 and 27 onward. The boundaries are conventions for talking about pregnancy rather than biological switches — nothing changes overnight at week 13 or week 27.

25 weeks pregnant

What happens at 25 weeks pregnant?

At 25 weeks a baby is around 34.6 cm long, from head to heel, about the size of a giant Easter egg. That is roughly 5½ months, in the second trimester, with about 15 weeks to go until 40.

Published length

34.6 cm long, from head to heel

In months

Roughly 5½ months

Trimester

second · 15 weeks to go

What is developing at 25 weeks

The baby responds to familiar voices and may startle at a sudden noise — the startle reflex has appeared. The hands are fully developed, and the nerves around the mouth and lips are becoming sensitive. Fat is starting to fill out the wrinkles.

The size comparison above is a giant Easter egg, which measures 35 cm top to bottom. Every comparison on this site is a real object with a real measurement, checked against the published length. The same week is drawn in seven other sets below, from Australian animals to fast food, if this one means nothing to you.

25 weeks, in eight rulers

Every other pregnancy tool measures a baby in fruit. This one offers eight sets to choose from, and each object below carries its real measurement, checked against the 34.6 cm the NHS publishes for week 25. Pick whichever ruler you actually have a feel for. Why not fruit.

Sweet treats
a giant Easter egg
35 cm top to bottom
Australian animals
a galah
35 cm beak to tail
The 90s
Tickle Me Elmo
35 cm head to feet
Sport
a tennis racquet's head
33 cm tip to throat
Things you already own
a shoebox
34 cm along the long side
Gaming
a tenkeyless keyboard
35.5 cm side to side
Fast food
a fourteen-inch pizza
35.5 cm across
Toys
a toy playhouse
35 cm base to roof

Your dates, from 25 weeks

Set to someone who is exactly 25 weeks today, so the due date below is the one that implies. Change the date to your own and everything follows from it — nothing is saved unless you do.

How far along am I?

Your due date

Do not know your due date yet? The due date calculator estimates one from your last period. A dating ultrasound is more accurate than any calendar method — if your pregnancy care team has given you a date, use theirs.

Questions about 25 weeks

How many months is 25 weeks pregnant?: 25 weeks is roughly 5½ months. Months are an awkward unit in pregnancy because they do not divide evenly into weeks — a calendar month averages about 4.3 weeks, which is why 40 weeks works out a little over nine months rather than ten. Appointments and scans are always booked in weeks, so weeks are the figure worth carrying.
How big is a baby at 25 weeks?: The NHS publishes around 34.6 cm long, from head to heel for week 25. Rather than one fruit, that length is offered here against eight rulers, each object carrying its own measurement: a giant Easter egg (35 cm top to bottom), a galah (35 cm beak to tail), Tickle Me Elmo (35 cm head to feet), a tennis racquet's head (33 cm tip to throat), and four more. Published lengths are averages across many babies, not a measurement of any particular one, and a scan estimate that differs is a normal thing rather than a finding.
What trimester is 25 weeks?: Week 25 is in the second trimester, on the commonly published split of weeks 1–12, 13–26 and 27 onward. The boundaries are conventions for talking about pregnancy rather than biological switches — nothing changes overnight at week 13 or week 27.

Where these numbers come from

NHS — Week-by-week guide to pregnancy — The published length of a baby at each week of pregnancy — measured head to bottom until week 20 and head to heel from week 20 — and what is developing at that stage.
Pregnancy, Birth and Baby — Pregnancy week by week — The Australian Government health service’s week-by-week account of how a pregnancy is counted and what develops at each stage.

General information only, not medical advice. BubSync is not a medical device: these tools do not diagnose, treat or monitor any condition, and using one does not create a clinical relationship. Every baby is different, and these are published ranges rather than targets to hit — they may not apply to your baby, particularly if they were born preterm, are small or large for their age, or have a medical condition. Never delay or disregard advice from a health professional because of something a calculator here showed you. If you are worried about feeding, sleep, weight or wet nappies, contact your child health nurse, midwife or GP — and if your baby seems unwell, floppy, or is difficult to rouse, seek urgent medical care now (000 in Australia).

Written by the BubSync editorial team. Not yet reviewed by an independent clinician. The editorial policy says who writes these pages and how their figures are sourced. Read how we write and check these pages.

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