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Baby age calculator and milestone calendar
Enter your baby's birth date to see exactly how old they are in months, weeks and days, and the date of every milestone photo in the first year: newborn weeks 1 to 12 and months 1 to 12. Then add all 24 dates to your calendar in one tap.
Pick a date and the results appear here straight away. Nothing is sent anywhere: the maths runs in your browser.
Let Little remember the dates for you
Little knows these same 24 milestones. It reminds you on each one, puts the right age badge on the photo, and keeps the year on your Home Screen. Free for iPhone and iPad, no account.
How baby age in months is counted
Months follow the calendar, not a fixed number of days. A baby born on the 8th turns a month older on every 8th, whether that month has 28 days or 31. That is how most parents count, and it is the date to take the monthly photo.
The month-end birthdays are the awkward ones. A baby born on 31 January has no 31 February, so their one-month date is the last day of February, and they go back to the 31st in March. The calendar above handles that and leap years for you.
Weeks are simpler: seven days each, counted from the birth date. Week 1 is the seventh day after birth, so a baby born on a Friday has every weekly milestone on a Friday.
What to photograph on each milestone date
Weeks 1 to 4
Sleeping shots on one plain blanket, with something for scale: a hand, a muslin, the same teddy.
Newborn weekly photo ideas →Weeks 5 to 12
The first real smiles. Shoot awake and fed, from directly above, at the same time of day.
How to take milestone photos on an iPhone →Months 1 to 6
Overhead on the same backdrop with a prop that shows the number. Rolling and grabbing make good captions.
Monthly baby photo ideas at home →Months 7 to 12
Sitting, crawling, standing. Write one line about what changed, then put the twelve together.
Milestone captions, month by month →
Short on props? The AI milestone photo prompts build a themed scene from a photo you already have, and the background library has a backdrop for every month. When the year is done, the twelve photos make a first year collage, and everything in between belongs in a baby scrapbook.
Baby age and milestone questions
How do I calculate my baby's age in months?
Count calendar months from the birth date: a baby born on 8 May is one month old on 8 June, two months on 8 July, and so on. For babies born on the 29th, 30th or 31st, a short month counts on its last day, so a baby born on 31 January turns one month on 28 February.
How many weeks old is a 3 month old baby?
About 13 weeks. A month averages a little over four weeks (30.4 days), so three months is 13 weeks and a few days. Six months is about 26 weeks, and the first birthday falls in week 52.
Should I use corrected age for a premature baby?
For development checks, doctors usually use corrected age (counted from the due date) until around age two. For milestone photos, most parents use the actual birth date, because the photos record the calendar months you lived through together. If you prefer corrected age, enter the due date instead.
Is my baby's birth date stored or sent anywhere?
No. The calculation runs in your browser, and the date and name you type are not saved or sent to us. The calendar file is made on your device too.
How do I get reminders for monthly milestone photos?
Tap Add all 24 dates to my calendar. On iPhone and iPad, Calendar offers to add every week and month as an all-day event with a 9am reminder. The Little app also reminds you on each milestone day without a calendar file.
Why does the calendar stop at week 12?
Newborns change fastest in the first three months, so weekly photos are worth it then. After week 12 the difference from one week to the next is small, and a monthly photo tells the story better.